Air Date: Week of October 1, 2021

A student cycling to school wears a mask to protect himself from smoke in the city of Palangka Raya in Indonesia. (Photo: Aulia Erlangga, CIFOR, Flickr, CC BY-NC-ND 2.0)

The World Health Organization is urging nations to adopt new air quality guidelines that could save seven million lives a year worldwide. In terms of the numbers of people affected, WHO says fine particulates known as PM2.5 are the deadliest of six types of pollution that need tighter restrictions. Much PM2.5 pollution comes from fossil fuel combustion, so reducing PM2.5 emissions would also benefit the climate. Host Steve Curwood is joined by Dr. Aaron Bernstein, pediatrician and interim director of the Center for Climate, Health and the Global Environment at Harvard University’s T. H. Chan School of Public Health.

Transcript

BASCOMB: From PRX and the Jennifer and Ted Stanley Studios at the University of Massachusetts Boston, this is Living on Earth. I’m Bobby Bascomb

CURWOOD: And I’m Steve Curwood.

The World Health Organization is calling for sharp reductions in air pollutants that kill seven million or more worldwide every year, including some 300,000 people in the US alone. On September 22 WHO adopted new and stricter guidelines for six different poisons that commonly pollute the air. These include carbon monoxide, sulfur and nitrogen oxides, low level ozone commonly found in smog, and medium and fine particulates. And it is those fine particulates known as PM two point five that lead to the bulk of early deaths, as these tiny but deadly toxins get sucked in through the lungs straight to the bloodstream where they circulate, just like oxygen molecules. And in the United States the allowable amount of yearly exposure to fine particulates is more than twice what WHO now recommends for all nations. We turn now to Pediatrician Aaron Bernstein, who is the interim director of the Center for Climate, Health and the Global Environment at Harvard University. Dr. Bernstein, welcome back to Living on Earth!

BERNSTEIN: Great to be with you, Steve,

CURWOOD: What are these new standards, and how do they match up to the former standards from the World Health Organization?

BERNSTEIN: So these new standards deal with a lot of the baddies in the air pollution world, the things we know that can be air pollutants that are really bad for our health, and they haven't been updated in a good long while. So one might argue that they're due for some revisions. And they're dramatic in many cases. So particulate matter air pollution, which is the pollutant that we see causing the most harm around the world, it gets defined by its size. So how big the particle in the air is determines essentially how bad it's going to be for our health. And the smaller particles are about two and a half microns in diameter, that's about 1/20 of the width of a human hair. And they've halved the safe level for the yearly exposure. They look at the levels in the air over the course of a year, and they also have a standard for a single day, so it used to be that the WHO said, if you had 10 micrograms per meter cubed of particulate matter, two and a half micrograms in diameter, you were okay. And now they're saying five. That's a pretty drastic reduction.

CURWOOD: So in terms of PM 2.5, talk to me about the implications of that, and just how many lives would be saved if that standard were, in fact adopted universally?

BERNSTEIN: Yeah, so we know that particulate matter pollution is responsible for millions of deaths around the world every year. And, you know, estimates vary, but a recent publication looked at just the particulate matter from fossil fuels, which, of course, is probably one of the bigger sources, if not the biggest source, depending on where you live. And it's estimated about 8 million people are dying from burning fossil fuels that produce particulate air pollution every year, that's one in five deaths. So we know that particulate pollution, particularly PM 2.5, is a big deal for death. And, of course, a host of other health problems, asthma, chronic lung diseases, heart disease, stroke, even lung cancer, and I could go on

CURWOOD: Now, some of the press material from the World Health Organization suggested that perhaps 80% of the deaths now from fine particulates would go away, if in fact, these standards are adopted universally. How does that strike you, Dr. Bernstein?

BERNSTEIN: Well, I think it's not implausible. I mean, we have for a long time underestimated how many people's lives were being lost from air pollution. And we know that so many people were living in polluted air, that was, you know, an excess of what the World Health Organization said, was safe, previously, and so ratcheting the level down, you know, we could save a lot of lives here. And the good news, of course, is that most of that air pollution in many parts of the world is coming from burning fossil fuels. And that means we have an opportunity to not only prevent those deaths today, but also help address climate change.

CURWOOD: So, talk to me about PM 2.5 and how that is related to, say, COVID mortality.

BERNSTEIN: Yeah, so this is a really important connection, Steve, and it actually goes beyond COVID. But there's now very clear evidence that people who've had to breathe more of this particulate matter air pollution, you know, over many years, are more likely to die from a COVID infection. In the United States, colleagues of mine at the Harvard Chan School found that people who had breathe just one microgram per meter cube more for many years, and remember the standard from the WHO was set down from 10 to five, in the United States, many communities will, you know, be in the five to 10 range. So one microgram is not a huge difference. But a one microgram per meter cubed increase in your many-year exposure to air pollution could increase your chance of dying from COVID by 6% or 8% in the United States. And the key part here to me is it's not just COVID. That same particulate matter, air pollution is going to increase your chance of dying from the seasonal flu, or from pneumonias or other respiratory infections. This has been known for a long time. And so it wasn't surprising to many of us to see that it was in true in fact, with COVID, which for many people is a problem for the lungs. So air pollution, and particularly particulate matter air pollution is a critical part of our health, outside of its direct effects on your chances of dying, you know, it could affect you know, how sick you get from a respiratory infection, it can affect our mental health, it can affect brain diseases. And so you know, you really get a lot of health benefits when you reduce exposures.

Every year, exposure to #AirPollution is estimated to cause 7⃣ million premature deaths and result in the loss of millions more healthy years of life.

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— World Health Organization (WHO) (@WHO) September 22, 2021

CURWOOD: So to what extent do the current air quality standards in the US match up with the new standards that the World Health Organization says we should adopt?

BERNSTEIN: It's a good question. It's kind of a mix and match. In some cases, the WHO standards are a little more stringent and in some instances they're less stringent. You know, for the particulate matter annual average, the WHO set a standard of five, and in the United States, we have an annual standard of 12. For ozone, we have a standard in the United States of 70 parts per billion. In the WHO standard, they have 60 parts per million. So, you know, for many of these pollutants and again for particulate matter, the evidence suggests that there's no safe level exposure. And so it really becomes a question of trade offs, which is how much can we reduce for how much money is it going to cost? And, you know, what's interesting is that, particularly in countries that have cleaned up a lot of air pollution, like the United States, even when you've done that, we still see when you look at the health effects and include the health effects and the costs of the harms the air pollution in your cost benefit, turns out that, you know, reductions below current levels are cost effective, that we actually would save money. The challenge is that when policymakers make rules, they're very quick to look at the cost of cleaning up the air, the benefits often are curtailed for a variety of reasons. And so we don't necessarily lower the pollutant levels to where the science would say. Now, we're never going to obviously get to zero in terms of particulate matter, because even if he got off fossil fuels, there'd still be things burning, there'd be secondary particles from other sources, even natural sources. But there's no question that there are many places, even the United States where particulate matter air pollution is a problem. And I should note that in the United States, you know, everyone has had better air quality over the last 40 years, the benefits have not been shared equally. So it turns out that white Americans have gotten improvements in their air quality more than Black Americans and Latinx Americans. And there's one part of the country and it is the only part that has seen a trend in the wrong direction. And that's in the northwest, where wildfire smoke has actually been so prevalent that the exposure particles has actually gone up.

CURWOOD: But wait, Dr. Bernstein, you're saying that the WHO level of five for fine particulates compares to 12 as the official US limit? Sounds like the US needs to think again about the particulate levels.

BERNSTEIN: Yeah, well, the science would certainly suggest that there are harms happening at levels below the current air quality standard. And, you know, the Clean Air Act in United States directs EPA to review the science and to set standards that are protective of health, including for vulnerable populations. And so we can expect that EPA is likely to lower the exposure standard for particulate matter, there was an effort already for many years now to lower the ozone standard as well. And there's a real political melee that happens, because, you know, polluters don't want to stop polluting so much, even if the pollution is causing pretty big harms. And again, there's a huge equity issue here, you know, it is in an era where we're all so focused on addressing, you know, systematic discrimination, it's hard to look at the data that makes so clear that if you're a Black American or Latinx American, not only are you exposed to way more of this pollution, because of where you live, and where those places are in relation to power plants and roads, you're the least responsible for producing it. And so it's this sort of double inequity. And so on the flip side of that, the more we can do to reduce pollution emissions, the more will see reversal of historical injustices. And so I'm cautiously optimistic that the more we shine light on these inequities, the toll that pollution from burning fossil fuels is having, the more political will we’ll see to get it even cleaner than it is.

CURWOOD: Aaron Bernstein is the interim director of the Center for Climate Health and the Global Environment at the Harvard T.H. Chan School of Public Health and a pediatrician at Boston Children's Hospital. Ari, thanks so much for taking the time with us today.

BERNSTEIN: Thanks for having me, Steve.

 

Links

Read more from the WHO about their new air quality standards

Harvard University: 8 million deaths from fossil fuels

The Guardian | “WHO Slashes Guideline Limits On Air Pollution From Fossil Fuels”

About Aaron Bernstein, M.D.