Wildfire Smoke Deaths in Canada Have Nearly Quadrupled

The smoke season is over for this year, and the orange skies have faded from memory for most of us. A new global health report says the toll those skies leave behind has grown dramatically, which makes the off-season the best time to prepare.

Deaths associated with wildfire smoke in Canada have risen by about 275 percent since the early 2000s, according to the Lancet Countdown on health and climate change. Global News and CBC News covered the major annual report this week. The report estimates an average of roughly 4,000 smoke-associated deaths a year in recent years through 2025, compared with about 1,050 a year between 2003 and 2012. Published in The Lancet and compiled by researchers around the world, it links much of the increase to human-caused climate change. It also found that 80 percent of Canada's heatwave days in 2025 were directly attributable to climate change.

Key takeaways

Yearly deaths associated with smoke from forest fires in Canada rose from about 1,050 in 2003 to 2012 to roughly 4,000 in recent years.

The 2026 Lancet Countdown also found that 80 percent of Canada's heatwave days in 2025 were directly attributable to climate change.

Fine particles in smoke travel deep into the lungs and bloodstream, which is why smoke affects the heart as well as breathing.

Older adults, pregnant people, young children, outdoor workers, and people with heart or lung conditions face the highest risk.

A HEPA air cleaner, well-fitted respirator masks, and an updated action plan are easiest to arrange in the off-season.

Why is smoke so hard on the body?

Smoke from burning forests is made up largely of fine particulate matter, particles small enough to travel deep into the lungs and pass into the bloodstream. That is why smoke is so hard on the body, and why it does more than irritate your eyes and throat.

Exposure is linked to asthma attacks, worsening lung problems, and heart trouble, and over time those effects add up across a whole population. Canada has seen a run of severe fire seasons, and the smoke from those fires has drifted far beyond the burn zones into major cities. People who never see a flame can still breathe its effects for days or weeks at a time.

Yearly deaths associated with wildfire smoke in Canada have nearly quadrupled since the 2003 to 2012 period

How do researchers count smoke-related deaths?

The way smoke-related deaths are counted matters for understanding the headline number. Ian Hamilton, a co-author of the report at Imperial College London, told CBC News that smoke may not be the single trigger in any one person's death. Across the population, though, more deaths show up during periods of smoke exposure.

In other words, smoke tends to push already vulnerable people over the edge, such as older adults or people with heart and lung conditions. The numbers appear in the population totals instead of on individual death certificates, which is why they can sound abstract until you know someone affected.

Heat compounds the problem, since smoky summers often arrive with hot ones. Our guide to the heat exhaustion symptoms you should not ignore covers the warning signs, and research on how heat waves may speed up biological aging shows why hot spells deserve the same respect as smoke.

Who faces the highest risk on smoky days?

The biggest takeaway is that smoke is no longer a rare event most Canadians can shrug off, since it has become a regular part of many summers. The risks on smoky days are highest for older adults, pregnant people, young children, people who work outdoors, and anyone living with asthma, chronic lung problems, heart conditions, or diabetes.

If you or someone in your household falls into one of those groups, a day of wildfire smoke is a real health risk worth planning for. The most useful steps are simple, inexpensive, and much easier to arrange in the off-season, when supplies are in stock and there is no rush.

What can you do before next summer?

Use the months before next summer to get ready, starting with the room where you spend the most time. These steps follow Health Canada's advice and cost far less to arrange now than in the middle of an air quality warning.

Set up a clean-air room. A portable air cleaner with a HEPA filter can noticeably clean the air in one room, and Health Canada explains how to choose one for your space.

Stock real respirator masks. Keep a few well-fitted N95 or equivalent respirators at home, since cloth and surgical masks do little against fine smoke particles.

Learn the air quality index. Bookmark Canada's Air Quality Health Index or turn on alerts in your weather app, so you know when to limit time outside.

Update your action plan. If you live with asthma, a lung condition, or a heart condition, ask your doctor before summer whether your plan needs changes, and keep inhalers and medicines filled.

Know the warning signs. During smoke events, trouble breathing, chest pain, a racing heart, or severe dizziness needs medical care right away.

Frequently asked questions

How does wildfire smoke affect your health?

Fine particles in wildfire smoke reach deep into the lungs and can enter the bloodstream. Short-term exposure can cause coughing, sore eyes, headaches, and asthma attacks, and it can strain the heart. Over a whole population, more deaths occur during smoky periods, mostly among people who are older or already living with heart or lung conditions.

Do surgical or cloth masks protect against smoke?

Cloth and surgical masks let most fine smoke particles through because they do not seal against the face. Health Canada advises a well-fitted respirator, such as an N95 or equivalent, if you must spend time outdoors in heavy smoke. Even a good mask reduces exposure without removing it, so limiting time outside still matters.

Does an air purifier help with smoke indoors?

A portable air cleaner with a HEPA filter can noticeably reduce fine particles in a single room when windows and doors stay closed. Choose a unit rated for the size of the room, keep spare filters on hand, and run it in the room where you sleep or spend most of your time during smoke events.

Your next step

If you have a lung or heart condition, a plan made in the off-season is worth far more than one made in an orange haze. The Medimap Health Hub has more on seasonal health, and you can find a family practice near you or book a walk-in clinic visit to talk it through.

Disclaimer: This article is for general information only and is not medical advice. It does not replace a conversation with a doctor or other qualified health professional who knows your history. If you think you are having a medical emergency, call 911 or go to the nearest emergency department.