Haze from the Canadian wildfires covers the Chicago skyline
Big Brains podcst

Why Air Pollution Is Cutting Years Off Our Lives, with Christa Hasenkopf and Anant Sudarshan (Ep. 95)

Scholars behind Air Quality Life Index report warn of threat to our global health

Haze from the Canadian wildfires covers the Chicago skyline
Big Brains podcst

Show Notes

We can’t always see the consequences of air pollution around us, but it’s costing us years off our lives. According to a new Air Quality Life Index report from the Energy Policy Institute at the University of Chicago (EPIC), air pollution is taking 2.2 years off the average global life expectancy. In some of the most polluted regions in the world, residents are expected to lose an average five years of their lives, if the current high levels of pollution persist.

While smog seem like a difficult problem to tackle, some countries have proven it’s possible to clean up the air. In the past seven years, China has reduced air pollution as much as the United States has in the past three decades. And since India’s Gujarat state launched the world's first clean air market in 2019, they’ve been successful in cutting particulate pollution by at least 20 percent.

In this episode, we speak with EPIC’s Air Quality Programs Director Christa Hasenkopf and EPIC’s South Asia Director Anant Sudarshan about why we need to treat air pollution as a global health threat—and what we can do about it.

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(Episode first published June 23, 2022 and republished July 6, 2023)



Paul: Many cities in the U.S. have been experiencing smoky and hazy skies lately.

Tape: Much of the east coast of the United States blanketed by smoke, drifting down from wildfires burning in Canada.

Tape: The tri state region is far from alone when it comes to unhealthy air quality. Americans in at least 18 states are being warned to stay indoors as much as possible.

Paul: Some of you have probably even been affected by poor air quality due to the ongoing wildfires in Canada that have been causing pollution to travel as far as Chicago, New York and beyond. 

Tape: Look at these incredible images. You can see the iconic Empire State Building shrouded in that orange phase. And the rest of New York City's skyline looks like we're seeing it through an orange filter.

Paul: On a previous episode of Big Brains. We spoke with some of the leading experts on air pollution about how this problem has been getting worse and the cost we're all paying for it. We're taking a brief summer break while we work on some special episodes, and we'll be back in August. But in the meantime, we wanted to share some of our best and most relevant episodes. These episodes contain some fascinating and life changing information for new and returning listeners. We hope you get as much out of them as we did. Thanks for listening.

Paul Rand: Wildfires smoke clouding the skies.

Tape: There are now 107 large fires blazing that have burned more than 2 million acres in 14 states.

Paul Rand: Vehicle emissions hovering over highways.

Tape: Experts have identified diesel cars as being partly responsible for the worsting air quality and increasing level of fine dust in this country.

Paul Rand: Factories burning fossil fuels day after day,

Tape: An invisible killer on the loose, responsible for millions of deaths.

Paul Rand: Air pollution is all around us.

Christa Hasenkopf: Air pollution is a huge public health threat, globally. And we don’t really treat it that way. At least not relative to the size of the problem

Paul Rand: And the devastating impact of that problem is far bigger than most people realize.

Christa Hasenkopf: It outstrips HIV aids, TB malaria, road injuries, war, and even smoking, when it comes to the size of the public health threat.

Paul Rand: That’s Christa Hasenkopf, director of the Air Quality Life Index at the University of Chicago’s Energy Policy Institute or EPIC.

Anant Sudarshan: It’s definitely a very serious problem. And it’s got sort of these invisible costs that are going to hold back development in all sorts of ways.

Paul Rand: And that’s Anant Sudarshan, the south Asia director of the Energy Policy Institute.

Anant Sudarshan: And so there is a communication issue in trying to get people to see the cost of pollution.

Paul Rand: We might not always be able to see just how dirty the air around us is. But it’s costing us years off of our lives.

Christa Hasenkopf: We lose on average about two years of our lives, globally, due to poor air pollution.

Paul Rand: But it’s not just that we’re also paying the financial costs for our dirty air.

Christa Hasenkopf: The global economy loses more than $8 trillion annually. That’s about 6% of global GDP to air pollution.

Paul Rand: From the University of Chicago Podcast Network. This is Big Brains, a podcast about the pioneering research and the pivotal breakthroughs that are reshaping our world. On this episode ,where air pollution is getting worse around the world, and how we can ensure that everyone has access to clean and healthy air.

Paul Rand: When you visualize air pollution, you might think of the great smog of London in the 1950s, the soot in the sky during the industrial revolution.

Christa Hasenkopf: I think we’ve all either seen pictures, or heard stories, or read Charles Dickens where there’s a blanket of smoke in the sky.

Paul Rand: But just because we can’t see visible clouds of pollution in the air, doesn’t mean it isn’t affecting us.

Christa Hasenkopf: I think it can be very easy to ignore air pollution. It’s invisible when it’s harming us, we don’t die from air pollution disease, but rather the issues that are come from downstream of it.

Anant Sudarshan: The people learn to ignore it, and that’s part of the problem.

Paul Rand: One of the ways that Hasenkopf, and the team at EPIC have been getting people to pay more attention to this crisis, despite it’s often an invisible nature, is with an annual public report called the Air Quality Life Index.

Christa Hasenkopf: So that report is a yearly report where we capture the health impact of air pollution for that year’s air quality across the globe on the length of a human life.

Paul Rand: And this year’s report was not reassuring.

Tape: The new study out of the University of Chicago says air pollution takes more than two years off of the average human’s lifespan. That’s more than causes like smoking, communicable disease, and war.

Paul Rand: But in some parts of the world, tragically, that number is much higher.

Christa Hasenkopf: So in our report, you can see that there’s a very large impact in south Asia, for example. So in India, there’s a average life expectancy loss of about five years.

Tape: Anyone venturing outdoors in the Indian capital, Delhi, today is taking a risk. Air quality chart state if they stay outside for too long, they could contract a respiratory illness.

Christa Hasenkopf: In Bangladesh, almost seven years.

Tape: Bangladesh has one of the world’s fastest growing economies, but it’s rapid urban development and heavy construction in the densely packed capital, Dhaka, has come at a cost. Pollution.

Christa Hasenkopf: In Pakistan, almost four years.

Tape: Pakistan’s, Lahor City has been declared the most polluted in the world, by an air quality monitor, as citizens continue to breathe in toxic smogs.

Paul Rand: And Sudarshan can tell you firsthand what it’s like to live with this problem in India.

Anant Sudarshan: Let’s say you were coming from a place like Chicago with relatively clean air. As soon as you step off the airplane, you’re going to feel like you’re breathing in a little bit of smoke. Your throat is going to get irritated. Your eyes might be watering. You also see it in things like if you run the Delhi half marathon, for example, it’s probably really bad for you. And a lot of people finish that race legitimately ill. They will have flu symptoms at the end of that, because they’ve spent a significant amount of time exerting themselves in poor air.

Paul Rand: For years, medical experts have warned about the impacts of dirty air on older people and immuno-compromised people. But now we’re learning about the impact on babies and kids.

Christa Hasenkopf: A recent report that looked at infant mortality founded about a half a million babies die each year in the first month of life due to air pollution as well. So these life expectancies are averages. It represents many forms of loss from air pollution.

Anant Sudarshan: I mean, there was recently a study which a prominent public health NGO did in the capital city of Delhi, where they found about 30% of school children had asthma and airflow problems. And so that’s just an astonishingly high number, and that’s directly coming from the quality of the air they breathe. It’s obviously even worse for infants exposed to those levels of pollutions.

Paul Rand: Dust. Soot. Smoke. Pollen. Even indoor air pollution. These particles are omnipresent.

Christa Hasenkopf: Particulate matter is just stuff floating in the air. It could be a liquid droplet. It could be a solid droplet. The issue comes about with the size of the particles. So, stuff like most dust or pollen, doesn’t really cause too much health harm, unless you have allergies, because your body can protect itself. When you breathe it in, it catches in your throat, your nose catches it. The problem happens when the particles are small.

Paul Rand: And one of the most worrying types of particulate matter is called-

Christa Hasenkopf: When we say PM 2.5, that’s particles that are 2.5 microns in diameters.

Paul Rand: And if you’re wondering just how small 2.5 micrometers is, think about a single hair on your head.

Christa Hasenkopf: 20 of those can fit across a hair, a piece of human hair. So they’re pretty tiny and they can invade really far into not just your lungs, but actually into your circulation, and affect your heart, and affect your brain. Pretty much every major organ in your body.

Paul Rand: And so if I’m breathing these things in, what kind of an impact is it actually having inside my body?

Christa Hasenkopf: So we often think of air pollution as causing respiratory issues, which it does. It causes lung issues. It can cause asthma attacks. But some of the most serious consequences of air pollution is that it can cause cardiac arrest. It can cause a heart attack. It’s been linked with even cognitive issues, like Alzheimer’s. There’s a wide array of issues that air pollution can cause in the body.

Paul Rand: One recent study in the UK found that if you were to live in an area with high levels of fine particulate matter for just one year, it would be the equivalent of smoking 150 cigarettes.

Christa Hasenkopf: Smoking cigarettes causes about a 1.9 year life expectancy loss. Whereas PM 2.5 pollution causes about 2.2 years. So they’re comparable.

Paul Rand: Particles less than 2.5 micrometers pose the greatest risk to our health. But even if you manage to avoid the worst of these particles, you’re not in the clear. Last year, the World Health Organization updated its air quality guidelines to include air pollutants that are actually greater than PM 2.5.

Christa Hasenkopf: So previously, the annual value that was considered safe to be exposed to for PM 2.5 was 10 micrograms per cubic meter. They changed that to half that, to 5 micrograms per cubic meter. In the US, our standard is 12 micrograms per cubic meter. And so half that is quite ambitious. And to put it in context in another way, this means that about 99% of the world’s population is breathing unhealthy air as classified by these guidelines. So they’re quite ambitious.

Paul Rand: At this point, you’re probably thinking of the highway across the street, or the factory up the road, and wondering where does all this particulate matter come from? Well, the main culprit won’t be surprising.

Christa Hasenkopf: The majority of air pollution’s health impact is coming from burning fossil fuels.

Paul Rand: In fact, according to one recent study, if the United States stopped burning fossil fuels, we could prevent an estimated 50,000 premature deaths due to air pollution.

Christa Hasenkopf: I’d say the big picture is that most of the PM 2.5 that poses a risk to human health is coming from burning of stuff.

Paul Rand: What often makes this problem so difficult is that in many parts of the world, there just isn’t one easy culprit.

Anant Sudarshan: Part of it is traffic and industry, both of which are sort of badly regulated. And part of it is people burning bio mass, because often they’re using that for cooking. So it’s a whole bunch of things. In a city you might have waste burning outside, because you don’t have good systems to collect and dispose of waste. So it’s a mix of different causes, which also makes it more difficult to build consensus because any one lobby or any one source can credibly say, “Well, the problem isn’t just us.” And so you almost need a big push on many dimensions and that makes it challenging to solve.

Paul Rand: Okay. But it’s not consistent, right? You could go from neighborhood to neighborhood, or country to country, or state to state, and find that the impact of air pollution is different in different places. Isn’t it?

Christa Hasenkopf: Absolutely. Air pollution and your exposure to it can be super hyper local. And it depends if you live near a highway, if you are near a coal burning fire plant. If you’re in a busy, highly busy trafficked area, you’re going to have hotspot of NO2, of nitrogen dioxide, from cars. In a more fine grain way, PM 2.5, a component of PM. 2.5 also can contribute directly to climate change as well. Solutions around climate change have huge overlap with solutions around cleaning up the air, too.

Paul Rand: Now you talked about this in terms of burning of fossil fuels. And I think we saw that even during the first year of the pandemic, there was less consumption of fossil fuels. Is that accurate? And has it continued?

Christa Hasenkopf: I was so curious what the end result, if you looked at the total pollution levels for 2020, what this would end up looking like. And so we look at that in our report, and we see just the tiniest decrease from 2019 to 2020, globally. I thought that was pretty surprising during that period, while there were lockdowns, there was also another part of the year where we were trying to overcompensate for that lack of production. And in some places, government restrictions around air quality were eased. So that production could be increased to compensate for that. So that could be play part of why that’s the case?

Paul Rand: According to the new Air Quality Life Index Report, air pollution continued to increase in south Asia during the first year of the pandemic. It’s clear that air pollution has a disproportionate impact on lower income communities around the globe. But unfortunately, communities don’t always have access to this data about their air quality. That’s where Christa says we need to bridge the gap.

Christa Hasenkopf: It is hard to find data in a lot of the hyper local situations where air quality can be the worst in the US. There’s not necessarily monitoring in those locations. It tends to be more spread out from the EPA. And so there’s a bit of a data gap. Even if you live in a highly polluted place, say a hot spot, it might not be on the radar for getting cleaned up. In, for instance, California’s exploring, they have this AB617 legislation that is helping communities, not only supporting them to put up monitoring themselves, but to also integrate that into their California’s emission reporting and monitoring in a more formal manner. So I’d love to see that scaled. For $10 million, you could fill a lot of gaps across the world, major countrywide gaps in air quality data across the world.

Paul Rand: The solutions to solving our air pollution problem are not that difficult in practice. In fact, one region in India is proving that it’s possible. Their solution and how it could be scaled worldwide after the break.

Paul Rand: When it comes to reducing air pollution, it’s actually not as hard as tackling something big, like climate change. In fact, Sudarshan has been working on what could be a new system for fighting air pollution. India’s first clean air market.

Anant Sudarshan: It’s a trading market. So you set a limit on the total amount of pollution that can be produced by a population of sources. But you let them trade permits so that they can distribute among themselves who’s going to do most of the emission cutting, and who’s going to do less.

Paul Rand: And this makes it much cheaper for the small companies and the manufacturers to cut pollution, without having to bear the burden of those costs all on their own.

Anant Sudarshan: If it’s really expensive for you to cut pollution, maybe because you are a small plant or there’s something idiosyncratic about your technology, then you can buy permits from someone else, which in effect is paying them to do more reduction themselves. And so that makes it cheaper, and that’s relevant, especially in Indian context. I mean, you always want environmental regulation to be cheap and efficient, but in a developing country where there’s this concern about possible trade off between environment and economic growth, it becomes all the more important to be able to cut pollution without imposing large costs on industry.

Paul Rand: In 2019, the team at EPIC launched the idea in India’s Gujarat state in a city called Surat.

Anant Sudarshan: Surat is a dense industrial city. It’s not the most polluted place in India, but a large part of the pollution is coming from industrial emissions, because it’s a manufacturing cluster for the textile industry in particular, which is also a significant source of pollution, because all of these plants are burning coal. Many of them are relatively small industries and do not have necessarily the ability to spend very large amounts of money on environmental abatement.

Anant Sudarshan: The Surat ETS was set up as a randomized controlled trial, which means we are in a position to very accurately measure what it actually did. In this case, it was really run almost like a large scale medical trial, where we had about 150 factories in the initial phase of the market, in a treatment group where they could trade permits and be in the market. And another 150 chosen at random, within the same city that were regulated using the status quo. So you’re very high quality evidence comparing like to like, of what the two forms of environmental regulation achieved.

Anant Sudarshan: The project is still ongoing, but we now have early results. And we think that emissions from the industries that were in the market have been cut by about 20 to 30%.

Paul Rand: Okay.

Anant Sudarshan: We see no evidence of an increase in costs. And the scheme is popular. So we’ve actually had industries asking to be enrolled in the market, factories in Surat, but also the program is now being scaled up across the state, both because it’s cut pollution, but also because industry actually prefers, or at least has been willing to consider this new form of regulation. I think that’s a political win. If you see 30% reductions in pollution from an important source and that source is not protesting about the policy, but willing and asking to be part of it. And that’s kind of why I think we’ve seen that scale up across Gujarat.

Paul Rand: Gujarat’s clean air market hasn’t targeted 100% of particular pollution, but if markets continue to scale up like this across the state, it could add years back onto people’s lives.

Anant Sudarshan: We’ve not cleaned up India’s air. That’s not something that is ever going to be achieved by one idea, tackling one source of pollution. But I think what the larger picture that these clean air markets prove is also the value of experimentation. But you’ve also proved that you can run a market and that Indian regulators can successfully execute this, and industry can understand this, and trades can be conducted on a secure platform. And so once you’ve done it for one pollutant, you can begin to ask, what about doing it for others? And CO2 is one. And so the scale up that you’re talking about, one is on the dimension of more clean air markets, and the other is on the dimension of different pollutants.

Paul Rand: India isn’t the only country using inventive measures to fight back against air pollution. One of the countries that has seen the most progress is, surprisingly, China.

Christa Hasenkopf: If we look at, say a longer term trend, from 2013 to 2020, we do see about a 10% improvement across the globe for particular pollution. But the thing is, is that most of that progress, actually, that entire progress can be captured by China.

Paul Rand: To understand how China tackled its smoggy problem, we have to go back all the way to January 2013, when Beijing experienced what became notoriously known as the air-pocalypse.

Tape: Beijing’s air quality has worsened dramatically in recent years. The first half of the year saw only two days in five with air deemed healthy.

Christa Hasenkopf: The air got so bad that it was a very visible problem.

Tape: Soupy skies envelope the city with a shroud of vehicle exhaust and factory emissions.

Christa Hasenkopf: And this was also around the time when folks were starting to get smartphones and had apps, and were getting real time information about the air quality. And so they weren’t just seeing it. This had happened before. But they were seeing it quantified in front of them. And seeing this is unhealthy air for you to be breathing. And that spurred a ton of media attention and public push for clean air around that time period.

Tape: The smog took on a name, the air-pocalypse.

Christa Hasenkopf: For the first time, there was access to open data that then app developers scraped from various sites and put on apps that millions of Beijing-ers saw. This stimulated all kinds of reaction from the media, including a journalist who ended up doing a landmark documentary on the impact of air pollution on her life and her child’s life, that had a huge impact too. And so it had all these knock on effects and really kept the momentum going, and pushed the government. So in 2014, they declared a war on pollution.

Tape: The war against the pollution is beating wage across China in north China’s Hubei Province, polluting iron and steel, and the salmon factories are being torn down. Notwithstanding many of them being pillars of local economy.

Christa Hasenkopf: This included policy changes, but also infrastructure to enforce policy changes, as well as huge increase in the number of monitoring stations across the country to actually measure that progress as well.

Tape: China’s 2013 action planning, set ambitious goals to reduce air pollution, including capping the share of coal in the energy mix at 65%, and reducing PM 2.5 emissions by 25% in Beijing, [inaudible 00:20:40].

Christa Hasenkopf: And so year on year we’ve seen a trend where there’s been improvement, and as I mentioned earlier, there’s been about a 40% reduction since 2013, which is something that in the US took decades to achieve.

Paul Rand: I guess in some ways, should we be a little bit more encouraged because there are places, i.e. China, that took this seriously and are seeing the benefits of it?

Christa Hasenkopf: I truly think the reason that China has been so successful is because there was such a large and sustained public outcry about air pollution. So I think the public’s engagement in air pollution made it an issue that couldn’t be ignored.

Paul Rand: One major difference between Sudarshan’s project and what happened in China, is that the Chinese government relied heavily on top down command and control measures. Whereas, he used market forces to drive down air pollution. And he argues that markets may be the better way to solve this problem, especially in countries that rely on industries for development.

Anant Sudarshan: It’s also the case that when you don’t have environmental regulation working, which is the status quo, you’re at risk of these extreme measures that could be implemented because say someone goes to the courts, for example, and says-

Paul Rand: Yeah.

Anant Sudarshan: ... “Look, there are all these plants. They’re emitting too much. The law says they need to be shut down. Shut them down.” And there have been cases in India where the courts have then made draconian rulings where, for example, in the capital city of Delhi, they just said, “All of these industries need to shut down and they need to move out of the city.” Right? And so those things are too few and far between to stop pollution from becoming a problem.

Anant Sudarshan: But they’re a big enough risk for industry that you’d rather have regulation that’s low cost, but predictable, than regulation, which you can ignore maybe, but which is sort of open to potentially corruption and open to these super strong kind of crackdowns that happen in unpredictable ways.

Paul Rand:

[inaudible 00:22:44].

Anant Sudarshan: And so that’s a measure of costs, which is not necessarily dollars and cents that you spend every year. But more a kind of cost of doing business in a predictable environment

Paul Rand: And market schemes for reducing air pollution have been tried elsewhere.

Anant Sudarshan: So, there’s never been a market tackling particulate emissions. But the United States did run a market that’s been credited with a lot of success, which was the acid rain scheme, which was targeted at a different pollutant, sulfur dioxide. One of the interesting things that has happened is that Gujarat is now announced that they plan to introduce India’s first carbon market. Now that doesn’t have to do with clean air, but a carbon trading scheme is something that United States, for example, has not been able to do nationwide. California does have one and it’s come, because part of the outcome is, did you clean up the air and reduce pollution? And that’s the main goal of the market as well. But you’ve also proved that you can run a market.

Christa Hasenkopf: We know the solutions for air pollution. They’re not rocket science. We’ve seen them implemented successfully in places like China, in the US, in large parts of Europe. So I think we know the ingredients to success in a lot of different contexts. It’s really just building up the local political will to do that.

Paul Rand: In addition to political will we also need the funding.

Christa Hasenkopf: Historically, air pollution hasn’t been super high on the radar or had its own dedicated bucket of funding. For example, about 0.1% of global philanthropic giving is devoted to clean air. That’s about $40 million. And I once read a stat that Americans lose more than that in misplaced pocket change each year. And so it’s very disproportionate relative to the harm it’s causing us.

Paul Rand: Although more and more philanthropies are donating to fight the climate crisis. There isn’t nearly enough money going to fight air pollution.

Christa Hasenkopf: Most of that money, most of the organizations giving that money, are coming from energy, climate, and environment organizations, not public health. So there’s a big gap, but I think one of the larger issues is that we need to find ways to make air pollution visible as a public health issue, and to get the public health community around that. And, I think academic public health community is already on board. They’re calling the alarm. But really to get the philanthropy and international development community engaged on air pollution is the real challenge.

Anant Sudarshan: But one of the things that our research group and that people in U Chicago and EPIC are doing is saying, “Okay, what have we actually proved? We’ve actually proved that if regulation isn’t working, you need to try out new things. There’s a systematic way of trying them out. Now, can we think of bright ideas for transport, for instance? Can we think of bright ideas for dealing with the burning of crops, which is a big source of pollution in winter?” And so that’s another dimension in which I think this program has kind of shown how researchers and policy makers can work together, and do so in a systematic way that moves the needle on very intractable problems that you sort of spent decades trying and failing to solve.

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