Scientists Push National Radon Testing and Screening to Fight Lung Cancer Risk

Health experts in Canada are sounding the alarm about the cancer risk posed by radon gas, an invisible, radioactive gas that can build up inside homes and other buildings. Radon is recognised as the leading cause of lung cancer among non-smokers and the second leading cause overall, after tobacco smoking.

Although radon occurs naturally nationwide, public awareness remains low and many Canadians have yet to test their homes for elevated radon levels. Health Canada and environmental health advocates estimate that about 16 per cent of lung cancer deaths in Canada are linked to radon exposure, equating to more than 3,000 deaths annually.

A growing body of research, including a national study of radon exposure patterns, has highlighted the potential to save lives by expanding radon testing and early lung cancer screening programmes. Some scientists are even exploring innovative methods — such as analysing biological markers from toenail clippings — to identify individuals with high lifetime radon exposure, which could help target more aggressive screening for those at risk.

Radon levels vary widely between homes due to soil chemistry, building foundation design and ventilation. The only reliable way to detect high indoor radon is to test with approved monitors or long-term detectors during colder months, when radon levels inside buildings are typically highest.

Public health advocates note that no radon level is considered completely safe, and that even below guideline levels, radon still contributes to a measurable risk of lung cancer. They argue that better national awareness campaigns, free or subsidised testing initiatives, and integration of radon exposure history into lung cancer screening criteria could help reduce radon-related mortality.

In addition to individual home testing and mitigation, experts say more data is needed to inform policy decisions and prioritise high-risk neighbourhoods for action. Improved building codes and structural measures to limit radon infiltration are also part of long-term strategies being discussed by health and environmental authorities.

Together, these initiatives aim to ensure Canadians better understand and manage the threat posed by radon, reducing the number of future lung cancer cases linked to this preventable environmental hazard.