[00:00:00] Sophia Gauthier: Welcome back. I am Sophia Gauthier. And I’m Graham Aufricht. We are pediatricians and hosts of this podcast, Clinicians, Kids, and the Changing Climate.

[00:00:10] Graham Aufricht: So we ended the last episode talking about wildfires. How does this lead into

[00:00:16] Sophia Gauthier: today’s topic? So today we are talking about the impacts that climate change has on air quality and respiratory illness.

Climate change contributes to declinations in air quality via three major ways, the first of which is wildfire smoke, second, ground level ozone, and lastly, pollen biomass.

[00:00:34] Graham Aufricht: So let’s start with wildfire smoke. Back in June 2023, as smoke from the Canadian wildfires blanketed the east coast, the air quality in New York City was ranked worse than any other city in the world.

What does this data tell

[00:00:49] Sophia Gauthier: us? So it’s estimated that every year in the United States, 7. 4 million children are affected by wildfire smoke. This is just the smoke, not including the wildfires themselves. Wildfire events also contribute to more than 2, 000 emergency room visits for children with asthma every year.

And as you probably know, asthma is the most common pediatric chronic disease. It affects over 6 million children in the U. S. alone. So

[00:01:14] Graham Aufricht: when we talked about extreme heat, you mentioned that there’s a link between those events… and increasing incidence of preterm birth. Is there similar data between wildfire smoke and pregnancy?

[00:01:26] Sophia Gauthier: Yeah. So exposure to fine particulate pollution is also linked to metabolic changes in pregnant women that’s associated with things like low birth weight and preterm birth.

[00:01:35] Graham Aufricht: Okay. You mentioned fine particle pollution. Can you tell me a little bit more about that?

[00:01:40] Sophia Gauthier: Yeah, so fine particulate pollution is classified based on size.

So as you can imagine, the smaller the particle, the deeper it can travel into your lungs and wreak respiratory havoc. Often the news discusses particulate matter that is less than 2. 5 microns in diameter. And you might see this annotated as PM 2. 5. This is because this very small size poses the greatest risks to respiratory

[00:02:04] Graham Aufricht: health.

Okay, so how do I apply this knowledge to

[00:02:07] Sophia Gauthier: my real life? Yeah, so as an example, I was living in Philadelphia a few years ago when we had multiple code orange days. This is where wildfire smoke from the west coast was so thick, it blanketed everything in this orange haze, kind of looking like, looking at the world through a sepia filter.

On these days, you know that the air quality is bad, so you can actually go online and check the local air quality index, or AQI. This is presented on a scale from 0 to 500. When the AQI is above 100, Sensitive groups such as people with asthma may start to experience health effects. The AQI in New York City back in June actually reached 342.

This is Dr. Elizabeth Matsui. She is a pediatric allergist, a professor for population health in pediatrics, and the director for the Center for Health and Environment Education and Research.

[00:03:00] Elizabeth Matsui: Smoke is air pollution. And we know a lot about what air pollution does to kids lungs and their respiratory health.

And of course, when there’s a wildfire event, the air pollution levels are super high. And we know in general that the higher they are, the more damage that’s done and the bigger the effect is. Um, on, and not just kids lungs. We’re talking about kids lungs because we’re both pediatricians. Um, and so it ranges from There’s an increased risk of visiting the emergency department for an asthma exacerbation, needing oral steroids, being hospitalized.

Um, for kids generally, not just kids with asthma, there’s an increased risk of emergency department visits and hospitalizations for respiratory infections as well. So it increases your risk of respiratory infection. So those are all acute events, meaning there’s high air pollution today, and so today, tomorrow, maybe the next day.

There’s an immediate manifestation of the effects of air pollution, um, on, on the lungs. But there are also chronic effects. Um, and so air pollution over time, um, can restrict lung growth. Um, and that’s a big problem because obviously it’s really important to have big, big lungs actually and you reach your peak sort of lung function in your 20s.

And you lose lung function every year after that at a rate of about 25 milliliters per year of FEV1. And that’s known on average. And so if you don’t reach as high a peak in your FEV1, um, then there’s, you have less sort of reserve as you’re losing your lung function over time. And then a word about wildfire specifically.

So one question is, I was just talking about air pollution. Well, is there anything different about wildfire air pollution? Um, and we think there is, and we think that it’s actually more toxic. So for the same level of wildfire air pollution relative to air pollution from other sources, there’s some emerging evidence that, um, it, it causes even greater effects on the lungs and kids

[00:05:12] Sophia Gauthier: respiratory health.

Climate change also leads to the production of ground level ozone, which is a main component of smog. This causes airway inflammation and damages lung tissue. So, ground level ozone is created when sunlight interacts with nitrogen oxides and volatile organic compounds produced from fossil fuel combustion in industrial facilities, motor vehicle exhausts, and gasoline

[00:05:37] Graham Aufricht: fumes.

Okay, and I’m guessing this has… Similar

[00:05:39] Sophia Gauthier: health implications? Yeah. The concentration of ground level ozone has massive implications for pediatric medicine. Exposure to smog is associated with asthma exacerbations, increases in both emergency room visits and intensive care admissions for asthma, as well as just an increased risk of developing asthma in the first place.

Good to know.

[00:06:00] Graham Aufricht: All right, we talked in the last episode about how children are uniquely vulnerable to extreme heat because of physiologic and developmental immaturity. Is this true with air quality as

[00:06:10] Sophia Gauthier: well? Yeah, children are uniquely vulnerable because one, they have higher minute ventilation than adults, and they also have physiologically immature lungs.

[00:06:19] Graham Aufricht: So we’ve talked about the impact of wildfires as well as smog on air quality. You mentioned pollen as well.

[00:06:25] Sophia Gauthier: Yeah, this one is super interesting. So global climate change also has a major impact on pollen count, which puts children affected by asthma and allergic rhinitis at risk for exacerbations. For example, the ragweed pollen season has already doubled in duration and may continue to increase in a predictive study In high emission scenarios, pollen biona mass is predicted to double from the year 2000 to 2060 by making aggressive cuts to admissions researchers in this.

study predict that pollen biomass could remain below 1. 5 times the amount in the year 2000.

[00:07:01] Graham Aufricht: We know that environmental allergies are a significant contributor to status asthmaticus. In 2021, 18. 9 percent of children in the U. S. had a seasonal allergy.

[00:07:12] Sophia Gauthier: Not only does warming climate contribute to longer pollen seasons with higher pollen mass, but also extreme weather caused by climate change can multiply this allergy effect.

What do you mean by that? So this is That’s also an interesting case. In November of 2016, residents of Melbourne, Australia witnessed the most dramatic episode of thunderstorm asthma recorded history. During just 12 hours, hospital admissions for asthma rose by almost 1000%, which absolutely overwhelmed the local healthcare system.

[00:07:45] Graham Aufricht: So what is the mechanism of thunderstorm asthma? So

[00:07:49] Sophia Gauthier: thunderstorm asthma only occurs in areas that already have extremely high pollen counts. When a thunderstorm approaches, whole pollen grains are swept into a maturing storm cloud by strong updrafts. High levels of humidity apply osmotic stress to these pollen grains, causing them to swell and then ultimately rupture.

And then these dry, cold outflows carry the pollen particulates back to the ground level.

[00:08:11] Elizabeth Matsui: And so normally pollen particles are large enough that for the large You know, part, they just stay in the nose or land on the eyes and cause allergic symptoms in the nose and the eyes, and they don’t penetrate into the lungs.

But the environmental conditions of a thunderstorm break them up, so they penetrate the lungs. And so, during an episode of thunderstorm asthma, there are people who may not actually have an asthma diagnosis, but they’re allergic to the pollen, or they have an asthma diagnosis, but it’s like incredibly mild asthma, where maybe You know, they haven’t needed an inhaler in a while or they rarely need their rescue inhaler.

Um, and then suddenly they’re inhaling more pollen into their lungs.

[00:08:54] Sophia Gauthier: There are actually about 20 episodes of thunderstorm asthma recorded globally in the last 30 years. Wow.

[00:09:00] Graham Aufricht: All right, so let’s talk key takeaways from this episode and opportunities for action.

[00:09:05] Sophia Gauthier: So climate change contributes To degradations in air quality via three main mechanisms.

One, wildfire smoke. Two, the production of ground level ozone and three increases in pollen

[00:09:16] Graham Aufricht: biomass. This is particularly concerning for pediatricians because asthma is the most common chronic pediatric disease. What can we do to help?

[00:09:25] Sophia Gauthier: First, I think pediatricians can give anticipatory guidance to families, teaching them how to look up and interpret local air quality indices as well as pollen counts.

We can

[00:09:33] Graham Aufricht: also help refer families for allergy testing or pulmonology evaluations so that they have the appropriate care plans for when poor air quality days or high pollen count days inevitably

[00:09:43] Sophia Gauthier: occur. And lastly, we can educate our families and our colleagues about taking environmentally friendly modes of transportation, such as biking or public transit, or even walking to cut down on air pollutants.

Okay, so that’s a wrap for today. Join us for our next episode on climate change and infectious disease. This podcast was researched and written by myself, Dr. Sophia Gauthier. A massive thank you to my friend and co host, Dr. Graham Aufricht, as well as Dr. Elizabeth Matsui for her expertise in pediatric allergy.

The podcast was produced by the fantastic audio engineers at the University of Texas at Austin Liberal Arts Instructional Technology Services team. with funding via a pediatric medical education grant and instructional support from the medical education fellowship at the University of Texas Dell Medical School.