MARY LOUISE KELLY, HOST:
This week it is hard to make out skyscrapers, hard to see past the bleachers in Wrigley Field, and for many, hard to breathe. I am talking about Chicago, which is blanketed in smoke from wildfires in Canada. Chicago claimed the world's worst air quality at one point this week. Well, to talk more about conditions in the city and the impact smoke is having on people who live there, we have called Dr. Ravi Kalhan. He is a pulmonologist at Northwestern Medicine. Welcome.
RAVI KALHAN: Thank you.
KELLY: So it's smoky today on the East Coast, too, but I gather nothing like what you were seeing, nothing like what you're breathing in Chicago. Paint me a picture of what it's been like there this week.
KALHAN: Well, it's been pretty awful outside. Just walking out the door, one could smell smoke. Someone I know described it as the smell of burning tires. And then, as you alluded to, visibility was really impaired. Like, normally, driving into the city, I can see the beautiful skyline and there was no sight of it over the past few days. It's a disconcerting feeling to not be able to see through smoke.
KELLY: So we can all smell, you know, we get a sense of what the burning tires smell like. I know here in Washington, I'm feeling my eyes burn and itch. But as a pulmonologist, walk me through the effect of all of this on a person's lungs.
KALHAN: Yeah. So what we're inhaling and smelling with the wildfire situation is wood smoke particles. So these are fine particles that actually get inhaled deep into one's lungs. Now, on the way into the lungs, they pass the nose and go through the windpipe and into the lungs. So anyone who's healthy even will feel watery eyes, like you mentioned Mary Louise, but also maybe some nasal irritation or a sore throat or a hoarse voice or even coughing. The particles can then get deep in the lung and cause an inflammatory reaction. So individuals who have chronic lung conditions like asthma or chronic obstructive pulmonary disease, COPD, can actually have flare-ups of their disease take place on the basis of being exposed to these particles. The other group that can be at risk are people who are prone to heart conditions. That inflammatory reaction that occurs in the lungs can set off an inflammatory reaction throughout the body, which has been associated with risks of having heart attacks and strokes.
KELLY: And we've been talking about people who may have underlying conditions or increased sensitivity. What about somebody who's 20, 30 years old, doesn't have underlying conditions? Is it at the point where you're saying, look; just don't go outside for a jog this week?
KALHAN: In general, these single-day exposures to someone who's a healthy young adult probably don't have a huge number of health consequences. But Chicago, the air quality index got almost to 300. So if someone sat outside for the full day in an air quality index of 300, that's like smoking half a pack of cigarettes. But the concerning thing is we're seeing more and more days like this. These aren't one-off experiences. And then we think about people spending large portions of their lifetimes, young adults or teenagers or children, being exposed to these things. In the long run, this creates a pretty significant potential public health risk.
KELLY: And is damage, any damage that may come from inhaling the smoky air, is it permanent?
KALHAN: Well, we don't know. It's really uncertain. We don't have a lot of information about the life course of respiratory health. This is something I'm actually working on actively, as I lead a 4,000 person young adult study where we're trying to follow healthy young adults throughout their lifetime. And it turns out that exposure to air pollution is one of our primary areas of interest. But we won't know for 20 years. It stands to reason, though, that inhaling chemicals and dusts into the lungs is not healthy. We know that from smoking, right? So I think that it's logical that this could have adverse health consequences. The increased frequency of these days is really worrisome. And in the long run, we'll have to understand how to better mitigate against the risk.
KELLY: It sounds like, you know, one consequence of this unfortunate situation is you're going to have a bigger study group to look at over those next 20 years as you try to figure out what this may mean for all of us.
KALHAN: That's true, although I would trade a clear day for that benefit (laughter).
KELLY: Indeed, wishing you clear days in the future and that the smoke may pass soon.
KALHAN: Thanks so much, Mary Louise.
KELLY: That's Dr. Ravi Kalhan. He is deputy division chief of pulmonary and critical care medicine at Northwestern. Transcript provided by NPR, Copyright NPR.