Front Burner - The true toll of wildfire smoke

Episode Date: July 17, 2026

As the planet heats up, wildfire seasons are getting worse. Wildfires have caused mass destruction to homes and community infrastructure in Collins First Nation. Thousands of people have been evacuated from their communities across Northern Ontario. Fires continue to rage across the country.Even those of us living in cities, safe from the flames, are feeling the effects. Toronto briefly had the worst air quality in the entire world this week, which led to government warnings to limit time outside, cancelled World Cup screenings and shutdowns of public pools. And it’s more than a nuisance. The Canadian Climate Institute estimates that wildfire smoke is associated with about 2,500 premature deaths per year across the country.David Wallace-Wells is a climate journalist and author of The Uninhabitable Earth. He joins us to talk about what it means that wildfire smoke is becoming a more regular part of our lives, and its place in the larger battle for clean air around the world. For transcripts of Front Burner, please visit: https://www.cbc.ca/radio/frontburner/transcripts

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Yeah. Hey, everybody, it's Jamie. When I woke up in Toronto on Wednesday, it looked like I was living on a different planet. The sky was orange. The air was hazy and smelled like a campfire. On social media, a video was circulating of a train stopped on the tracks in northern Ontario, surrounded by flames like it was frankly driving through hell. Okay, you all need to hurry up here.

Like seriously, we're encased in flames now. Not far from that scene, wildfires cause mass destruction to homes and community infrastructure in Collins' First Nation, and thousands of people have been evacuated from their communities in the region. As the planet heats up, wildfire seasons are getting worse. And even those of us living in cities safe from the flames are feeling the effects. Toronto briefly had the worst air quality in the entire world this week, which led to government warnings to limit time outside, canceled World Cup screenings and shutdowns of public pools.

And it's more than a nuisance. The Canadian Climate Institute estimates that wildfire smoke is associated with about 2,500 premature deaths per year across the country. So today, we're going to talk about what it means that wildfire smoke is becoming a more regular part of our lives and its place in the larger battle for clean air around the world. David Wallace Wells is a climate journalist and author of The Uninhabitable Earth. David, it is really great to have you back on the show.

Thank you so much for making the time. My pleasure. Thanks for having me. So Toronto, as I mentioned, briefly had the worst air quality in the world earlier this week. But I'm about four and a half hours away from the closest fire. The next closest big one is in Quebec and is like an eight-hour drive. And I wonder if we can start with what it's like when you are right up close, putting aside. the actual flames. Talk to me a bit about the smoke impact closest to the actual fires.

Well, it can be incredibly oppressive. It can make it incredibly hard to, you know, move around outside comfortably. But the most significant effects are still relatively long term as opposed to acute. You do see, you know, big spikes in hospital admissions right around the arrival of a big fire and smoke effects. But when you look at the way that cancer rates increase among wildfires, fighters and the way that communities that we're dealing with a big burst of wildfire smoke have their health affected not just for days and weeks, but for months and years. I think those are ultimately the most concerning largest toll health impacts. The immediate experience, I think, is typically dominated less by the smoke and the difficulty

breathing and much more by the sheer terror of flames like some of the scenes that you're describing in which we are now seeing, unfortunately, more and more often. I'm, you know, I'm an American. I think these days most often about the Los Angeles fires from last January, but these are events that are happening not just more and more frequently. They're not just burning more and more land, not just tearing up, you know, more and more landscape and turning it into smoke that we breathe,

but also burning through relatively densely populated communities and producing some quite tragic, horrifying results. Not far away Monday, residents and Namibusasegagan First Nation were forced out, some by boat. The community home to about 130 people destroyed. Growing wildfires in Manitoba have prompted evacuations. The firefight is underway in the Northwest Territories. A massive blaze continues to threaten the village of Fort Simpson.

Another is threatening the community of Wrigley. The fire burning in British Columbia's Fraser Canyon has led to, to the evacuation of three communities, while a fourth is on alert. More than 800 fires are burning across the country. The vast majority are out of control. It's devastating to watch, as it is, every summer now. As I mentioned, in Toronto, I can see the haze and smell the smoke. Across Ontario, orange-tinted skies.

The smoke from wildfires burning in the province's northwest, prompting environment Canada to issue a severe air quality warning. the smoke also drifting across the U.S. border. How does the impact of the smoke change as the distance increases? The distance itself is one factor. There's also the relative height. So at certain times, in certain places, wildfire smoke traveling hundreds of miles can be relatively high in the sky.

It can produce really eerie cinematic effects without even necessarily impacting much the health of the people on the ground. And then in other places it can descend, much lower and become something that we all breathe in. And so there's also, there's a strange way in which our perception may not be the best indicator of how safe it is to breathe the air. And in fact, a lot of the technical measures that we might check on our phone for air quality, those are also at best and complete. And so, you know, among the other things that makes this a sort of worrying, anxiety-producing experience is that it's very hard to come by reliable

information about how serious the threat is to one's health. In general, the closer you are to a fire, the more vulnerable you are to the effects of smoke, but the smoke can be carried quite a long ways. You mentioned the air quality in Toronto, but today, some of the worst places in the world are in Detroit, in Chicago, yesterday in New York, where I am registered quite worrying levels. and we've seen from previous wildfire seasons that smoke can travel across the Atlantic Ocean, from even the west coast of Canada, across the Atlantic Ocean all the way to Europe. We've seen Australian bushfires travel not just to New Zealand, but all the way across the much larger Pacific Ocean to Latin America, South America.

And so, you know, depending on the wind patterns, you can be literally halfway around the world and still suffering as a result of great fires that are far, far away. And that is, I think, one additional thing that most of us living in cities like Toronto and New York haven't really yet reckoned with, the idea that we may not come face to face with fires ourselves, but fires that are hundreds or even thousands of miles away

can be imposing really serious consequences for ourselves and those we love. I know you said it's hard to kind of gauge how dangerous it could be. But, I mean, just tell me more about what we know about how dangerous is wild. fire smoke that spreads could potentially be. Is it more harmful than other pollution less, for example? Well, you know, a lot depends on what's actually burning. And one of the kind of confusions at the moment about the way we talk about these fires, that we group a lot of things together. So, you know, a couple years ago in the 2023 fire season, I was up in Yellowknife, I'm looking at what had happened with the Northwest Territories there. That fire, it's basically all trees

that are burning. I mean, there are some communities that suffer. and were damaged as a result. But in terms of the mass of fuel that was being turned into smoke, it was almost entirely wood and tree. When you think about what happened in Los Angeles last January, something very different. Some people have called it the return of the urban firestorm. What we're seeing there is that is not a fire that's in the wildland breaching into some small community.

It's a fire that really takes the community, the built environment, as the fuel. And as a result, turns all of that built material into what we're breathing. So when we talk about what happened in the palisades or in Altadena, we're not even really talking about brush fire or trees being burned and then being breathed. We're talking about breathing in the residue of bicycles and refrigerators and cars and insulation and vinyl siding. There is some wildlife in there, but there's also an enormous amount of quite corrosive toxic stuff that we're breathing in. And so a lot depends on what actually goes into the fire to determine how unhealthy it is, you know, coming out the other side. In general, it's believed that wildfire smoke on a sort of per dose basis is worse for you than most conventional air pollution. I should say, at the global level, is an incredible killer.

We're talking about five to 10 million people a year dying from the exposure to air pollution. in certain parts of the world, you see across the Gangetic Plain in India, people having their life expectancy cut by five years or more from these effects. In places like Canada, the U.S. and Europe were on more of a recognizable downslope. We're exposed to less industrial air pollution than we were in a previous generation. But we're starting to see those gains, which we had kind of banked emotionally, come undone because of the effects of wildfire. And the effects on health they're really quite notable. You mentioned one estimate of the Canadian death toll estimated in a couple thousands. Other estimates are considerably higher. In the U.S., some estimates suggest something like

20,000 people dying every year from the effects of wildfire. Some are higher than that. And then if you project into the decades ahead, sort of best in class gold standard science suggests that we will be seeing something like in the U.S. 70,000 deaths a year in the second half of the century because of exposure to wildfire and smoke. So it's a quite significant public health threat. Thankfully, in most cases, it's relatively time limited, which means we can take certain kinds of precautions, knowing that in a few days we can undo those. But in other parts of the country and in the world, the kinds of risks that used to impose themselves for just a few days are now imposing themselves for weeks or months, and that becomes considerably

harder to shoulder that burden. Right, to stay indoors. wear masks. Yeah. Well, the mask thing, I have been seeing people walking and riding around wearing those N95 masks that we held during COVID, which was, you know, not a great flashback, to be honest. But does that help? Does that make a difference? Yeah, I think the basic rule of thumb is the intuitive one. The less of the smoke that you can breathe in, the better off you are. And I should say that in general, you know, I think we have a intuition about some of these risks, because they appear so apocalyptic, we think of this as poison. And in a certain way, it is.

There is poison being carried by the air into our lungs. But there's a lot of stuff we breathe every day that's quite bad. People in cities like Toronto and New York used to breathe quite poor air quite a lot in the 60s and 70s when we had a lot more industrial pollution. And so we shouldn't think of this risk as like when we walk outside, we take one gulp of air and we're going to have a dramatic health event as a result. it's more of the kind of thing that you imagine being notable at the population level, where you see some significant number of additional asthma cases reporting to emergency rooms and people with respiratory conditions suffering more. And those are real public health costs.

I don't want to minimize them. But it is the kind of thing that happens at the population level much more than it seems to affect you acutely. And at the individual level, you should, I think, relate to the threat in the same way, which is to take precautions that limit the amount that. that's going into your lungs without straining to prevent every single ounce of smoke particle from getting in there. Because a few breaths of air between your front door and your car or whatever are not going to be all that bad for most people. But that means that to the extent you can stay indoors, that's better.

To the extent that you can use air purifiers inside, that's good as well. And to the extent that you can wear a mask, that's helpful. This week on two blocks from the White House. From Lindsay Graham's sudden death to Mitch McConnell's absence and Graham Plattner's campaign collapse. This week we're asking, with the midterm elections only months away, what is going on with the Senate? Join me, Willie Lowry, and my fellow Washington correspondence, Paul Hunter and Katie Simpson, as we break down U.S. politics from a Canadian perspective. Find and follow two blocks from the White House wherever you get your podcasts.

And watch us on YouTube. New episodes drop every Wednesday. I wonder if we could zoom out a bit more now to talk about air pollution globally, more generally. And it's just if you could tell me more about what the biggest sources of air pollution globally are right now. Is it energy? Is it farming? Yeah. It's a little misleading to talk in the global scale because different countries have different mixes.

And so in different parts of the world, the causes are really distinct. and the solutions that if we want to take action are also different. But generally speaking, globally, the biggest source is the burning of fossil fuels. You know, the same thing that is cooking our planet is also torching our lungs. In the parts of the world where air pollution is worst, notably South Asia, and to some extent sub-Saharan Africa, parts of sub-Saharan Africa, the effects of agricultural burning and, in fact, biomass burning inside the home, which is to say cooking with unclean fuels are really significant contributors to the mortality burden overall. But if we're taking stock of the global picture,

it's sort of the same story as global warming. The same thing that's causing that is causing this. We're seeing this huge push right now for data centers. This Alberta County less than an hour outside Edmonton, soon to be home to a massive AI data center. But in towns near the future site, Residents have mixed feelings. I just don't know about the impact. A study from Cornell found that AI growth could put an additional 24 to 44 million metric tons of carbon dioxide into the atmosphere by 2030 in the U.S. alone, which is the equivalent of adding 5 to 10 million cars on the roads. And just put that into perspective for me. What could this data center push mean for air quality?

Well, a huge amount depends on what we use to produce. the power for those data centers. And that is still being determined and shaking out. You know, if we were to devise ways to use clean power, it would have no effect. And to the extent that we're using natural gas, it will have a medium effect. And to the extent that we're using coal, it will have a significant effect. And so all of that is up in the air. And there are people working and trying to design policies to make sure that data centers are as clean as they can be, as opposed to as dirty as they can be. I would also say, you know,

the numbers that you cited are striking when considered from a baseline of zero. But if we're talking about the equivalent of adding five million cars to the road, the U.S. has hundreds of millions of cars on the road already. So the data center story is a significant one. It's producing a huge political backlash in the U.S. There are environmental concerns,

but there are also political concerns, their economic concerns, existential concerns, all of those are beating into the backlash. And so it's a bit of a complicated picture. I would say that locally, if you have a data center, especially one that's like running on coal power, but maybe even if they've built a new natural gas facility to power them, you may be dealing with some significant additional air pollution in that area.

And that may be one real reason to fight that project. But at the national level or the global level, I think the data center story is a secondary one. And we're still talking about in bulk, you know, fossil fuel problems and this sort of more erratic but quite concerning spike in wildfire smoke and emissions. You know, I want to ask you about efforts to curb air pollution. The Chinese government declared a war against air pollution in 2014, right? After this very smoggy winter. And that was followed by actually a steep drop in particulate pollution.

It fell around 40% by 2023. And just how did they do that? They did a few different things. One big thing is they moved all their coal plants just farther away from Beijing. So they didn't close them all. They are in some way moving towards a post-cold electricity system, although not all that rapidly. But in the meantime, they just moved the production away from people to make the exposure considerably less. They took some measure to – some initiatives to –

filter the air that was coming out of those plants. And they also have begun to roll out green electricity in a much more dramatic way. China's economic miracle was fueled by one thing, coal. But in 2025, a critical threshold was crossed. For the first time, the combined capacity of wind and solar in China surpassed coal. In almost every part of this country, building a new wind or solar farm, is now cheaper than running a coal plant. They've also done some amount of kind of geoengineering

to try to prevent what pollution there is from approaching population centers. But I think the main thing is just moving the coal plants farther away, fitting them with some kind of air filters and trying to green the electricity system generally rather than plunging headlong into the coal future. Yeah, do you see China as a kind of model? There are a lot of different models,

Yes, I mean, in general, I think it's interesting that an authoritarian government that is not democratically responsive to its population may have moved faster to alleviate the health burden of pollution than we've seen in any democratic country in the world. You know, that's maybe an irony, maybe it's a paradox. You know, it used to be that the American cleanup of our air in the 60s and 70s was cited as the gold standard. And it's still quite impressive. I think the benefits of the Clean Air Act have been calculated in the tens of trillions of dollars. And at, you know, 30 to 50 times more benefits than the cost of undertaking that program. But we still have more progress to make. And as I was saying a few minutes ago, the wildfire effects are erasing many of those gains,

which means, you know, it's not just that we shouldn't be sitting pretty and patting ourselves on the back for where we are. And then maybe thinking of doing a little bit better, we actually have to take proactive. action to prevent things from getting worse from where they are. We're also watching this push, though, from the Trump administration to reverse a lot of environmental regulations. Where do you see the U.S. right now when it comes to clean air? Well, I think that the Trump administration has been an unmistakable villain when it comes to climate.

It's the greatest con job ever perpetrated on the world, in my opinion. Climate change, no matter what happens, you're involved in that. When it comes to health, when it comes to science, but maybe the most visible crime against humanity that they've imposed on their population is this across-the-board effort to weaken oversight and regulation of environmental contamination. Whether it's mercury in the air or, you know, chryogenic pesticides sprayed on food, they are at every point doing what they can to weaken protection. for American citizens and enable corporations to do more damage that they previously were unable to do. Ultimately, that is taking place in a policy context. There's also an economic context. And it is not the case that, you know, Trump's rollbacks of these protections have already imposed

1960s level pollution on America. I don't think that would happen even if these rollbacks were permanent and lasted for decades, just because the public wouldn't tolerate it. But unfortunately, I think we're likely to see considerably more health consequences from some of these actions in the years ahead as the effects accumulate. I want to come back squarely to this issue of wildfires. I mean, if you're trying to address just that issue alone, the fires and then the smoke that comes from them,

what is the answer there? So I don't want to sound too far. fantastic. But I've been on a bit of a journey myself on this question over the last few years, and the whole problem seems much harder than I thought it was just a few years ago. And what I mean by that is, you know, you get smoke from fires when fires burn. So the main way that you can control the distribution of smoke, the production of smoke, is by taking control of this fire problem. And a few years ago, I was persuaded by a lot of fire scientists who said that especially in the U.S., but to some degree in Canada as well, we had made this problem for ourselves by fighting fire so aggressively over many decades that there was now this huge buildup of fuel on the landscape. And that we could address that to some extent through smart logging practices, through some extent through prescribed burns, indigenous burning practices.

and that that would allow us to really limit the ultimate fire risk on the landscape. And that seemed persuasive to me. But what we've seen over the last few years has really given me pause. And by that I mean, for instance, the 2023 fires in Canada burned mostly in areas that had never had any firefighting in them in the remote boreal forest. This is not the result of human action, which means it's hard to understand how human action could limit it in the future. future. They are largely uninhabited areas, which means it is extremely hard to fight them, even if we wanted to. And again, we have these scientists telling us, in some cases, we don't want to fight those fires because we want the forests to regenerate through fire

as they should naturally. In America, we've seen prescribed burning that actually got out of control. You know, fires that were set on days that we thought were safe, the fire actually escapes containment and turns into, you know, some of the biggest, largest fires in state history. There's also been all of this political opposition. People don't like fires in their neighborhood, even if they're told that they're safe. And so the challenge of getting us up to the scale that we would need to of prescribed burning to bring the landscape back into a kind of an equilibrium, that seems really intimidatingly hard. Yeah. I mean, I guess the thing I have been seeing online in the last couple of days is an anger about, you know,

know, a lack of commitment to climate goals, right? And I just wonder if you could address that, like, that connection that people are making between climate action and what they're experiencing. Yeah, I mean, I think we're seeing it sort of across the board. There has been a notable decline in apparent climate concern. I think the surveys sort of tell a somewhat different story, but if you look at the headlines, you look at television news, climate change is just not the top shelf issue that it was just a few years ago. Few politicians are talking about it in existential terms like they were four or five years ago, including Mark Carney, who was a brave climate leader for a long period in his life and has made promotion of the extraction of fossil fuels, one of the central projects of his. of his time in office now?

The goal remains the same, but as times have changed, we must change our plan to get there. We can't afford to restrain the growth of an important part of our energy mix, oil and gas, to meet a short-term goal. I want to be clear on this point. The changes we have made will mean that our emissions will be higher in the next few years than they were projected to be under the previous government's plan. But in my judgment, that plan was not sustainable over the long. long term. But that isn't exceptional or unusual. You're seeing that kind of backsliding among many

leaders all around the world. The wildfire problem, like many climate impacts, is a complicated one to detail or describe in terms of climate action because, you know, the United States, whatever it does is probably going to have a much bigger impact on Canada's climate than Canada will. certainly Canada's climate action is going to be small compared to the effect of the entire rest of the world on Canada's climate. And that means that the levers are relatively weak for any individual country trying to take control of any individual impact. But that's one reason why we need to do all this together rather than thinking in narrowly nationalistic terms. I think it's one of the big costs of the political changes that we've seen around the world over the last five or six years or maybe you could say 10 or 12 years in which more people are thinking

in individualated nationalistic terms, not thinking about the global community. And you see, you know, I've seen in my social media over the last few days, a lot of Americans yelling at Canada. A group of Republican congressmen just wrote Mark Carney saying basically like, get your act together. Yeah. And that we saw that in 2023 too when this happened. I mean, I think there's actually, the media is a little bit at fault where like people are so aggressively calling these Canadian wildfires. Dangerous smoke from Canadian wildfires. Dangerous smoke from Canadian wildfires.

Dangerous smoke from raging Canadian wildfires. Canadian wildfire smoke invading the nation right now. I keep saying to my friends, like, there's a lot of fire in Minnesota, too, that's happening right now, not to mention fires all around the U.S. And it's a complete political evasion. It's irresponsible. And it's intellectually disingenuous. Mark Carney is not right.

responsible for the fires burning in Canada. Canada's firefighting forces are not responsible for the fires now burning in Canada. The forces that are producing that risk are global and the U.S. is a major, you know, we're the number two contributor. So, you know, we have this instinct in the moment of disaster to try to pin the blame on somebody because we don't want to acknowledge that the system as a whole has gone completely. completely haywire and is subjecting us to risks that we never thought we would have to tolerate. David, thank you so much for this. Really appreciate it. My pleasure. Thanks for your time and talk to you guys soon.

All right. That is all for today. Front burner was produced this week by Joythe Schengupta, Matthew Almaha, Kevin Sexton, Sam McNulty, Dave Modi, and McKenzie Cameron. Our YouTube producer is John Lee. Our music is by Joseph Shabbison. Our senior producers are Elaine Chow and Imogen Burchard. Our executive producer is Nick McCabe Locos, and I'm Jamie Poisson. We'll be back next week. Thanks so much for listening. For more CBC podcasts, go to cbc.ca.ca slash podcasts.