Our lung health and air quality experts explain the hidden risks of smoke exposure and how emerging research is shaping what we know about the health impacts of smoking.
Whether you smoke or not, exposure to second- and third-hand smoke can have lasting effects on your lungs. Research is uncovering the invisible risks tied to cancer, respiratory disease and other health concerns.
Vancouver Coastal Health Research Institute researcher Dr. Milan Khara and Lauren Wilkinson, Tobacco and Vapour Reduction Program coordinator, shed light on how the air around us affects our well-being.
Q: What is second-hand smoke, and how is it different from third-hand smoke?
A: Second-hand smoke is the nearby smoke produced when someone else uses cigarettes, cigars or pipes. People who breathe in this smoke are exposed to many of the same harmful chemicals and fine particles inhaled by the person smoking.
Third-hand smoke refers to the residue that settles onto surfaces such as skin, clothing, carpets, walls and furniture. It can remain long after smoking has stopped. People can be exposed by inhaling lingering odours, touching contaminated surfaces or absorbing chemicals through the skin. Young children and pets are particularly vulnerable because of the time they spend close to floors and surfaces.
Q: Does second-hand smoke affect my lungs, even if I don’t smoke myself?
A: Yes. Many of the serious health risks associated with smoking come from breathing in the chemicals and particles in tobacco smoke. Someone exposed to second-hand smoke breathes in these same toxic components.
Second-hand smoke increases the risk of chronic cough, chest infections, asthma, chronic obstructive pulmonary disease and lung cancer. Children, pregnant people and those with existing lung conditions experience greater risks from second-hand smoke exposure.
Q: How does third-hand smoke linger in a home or public spaces, and what are the potential health impacts?
A: Third-hand smoke can remain on surfaces for years and is extremely difficult to remove. It can even be detected in indoor environments where smoking is no longer permitted because residue persists from past exposure.
We know third-hand smoke contains nicotine and other substances linked to increased health risks, including cancer. Research is ongoing to better understand its long-term health effects.
Q: How can I have an open, empathetic conversation with family, friends or neighbours about the risks of smoke exposure?
A: These conversations can be sensitive, especially if the person is not ready to quit smoking. Approach the discussion calmly and without judgment. Share your concerns clearly but avoid lecturing. Listen actively and be patient — change often requires multiple conversations.
Resources such as the CAMH tip sheet on managing second-hand smoke and the HealthLinkBC information sheet on second-hand smoke can guide supportive and respectful dialogue.
Q: What systemic changes and public policies are needed to ensure that everyone has equitable access to smoke-free spaces and evidence-based support to quit smoking?
A: More than 90 per cent of British Columbians don’t smoke tobacco, and many public places in B.C. are already designated smoke-free. However, the home remains a major source of exposure, especially for children. A recent Canadian study found that non-smoking children and adolescents had the highest exposure to second-hand smoke of any age group. Non-smokers living in apartments were also far more likely to be exposed than those in detached homes.
At the community level, multi-unit housing can adopt smoke-free strata bylaws or building-wide policies. At a broader level, the province could consider requiring new multi-unit buildings to be smoke-free.
People who smoke have access to some free, evidence-based supports in B.C., including QuitNow, Talk Tobacco and free nicotine replacement therapy through the BC Smoking Cessation Program.
