SCOTT SIMON, HOST:
Wildfires in the Seeley Lake area of Montana this summer were longer and more intense than any in recent memory. Though they didn't reach B.J. Leiderman, who writes our theme music. Nora Saks with Montana Public Radio reports that the long fire season has given scientists a chance to study something they actually don't know much about - how prolonged smoke exposure affects people.
NORA SAKS, BYLINE: Jean Loesch and her family live right in Seeley Lake, which had the worst smoke. She has 10 kids altogether. All are adopted or foster children.
JEAN LOESCH: So this is Hayden (ph). This is Perry (ph). This is Ally (ph). They're twins.
SAKS: Loesch says that during the summer, the smoke was so thick outside that they couldn't see the trees across the street. So they stayed inside. And it was still really hard to breathe.
LOESCH: These guys were miserable. Each one of them ended up having to going to the doctor. Everyone had a puffer.
SAKS: She says most of her kids didn't need inhalers before. And her family is usually pretty healthy but not this year. Loesch says she got pneumonia. The kids had bloody noses. And now, even with the smoke long gone...
LOESCH: They'll wake up hacking. They've all been sick, whether it was a cold - I've had to take them in for upper respiratory infections.
SAKS: The 2017 wildfire season lasted from the end of July through mid-September. Rachel Hinnenkamp with Montana's Health Department has been tracking how many people went to emergency rooms complaining of respiratory-related symptoms during that time. And the number more than doubled for people who lived near active wildfires.
RACHEL HINNENKAMP: The number of visits in 2016 was 163. And that increased to 378. So that's a statistically significant increase.
SAKS: She says it's too early to say whether all of those ER visits were directly related to the long and severe wildfires this summer. But most came after the fires had been burning for about a month. The more you're in polluted air, the worse your health gets. But no one knows exactly what Montana residents can expect in the long run from this past season.
SARAH COEFIELD: The smoke that we saw this year in Seeley Lake was like nothing we've ever seen.
SAKS: That's Sarah Coefield, the air quality specialist for the Missoula City-County Health Department. The EPA says concentrations of fine particulate matter in the air above 35 micrograms per cubic meter is unhealthy. Coefield says this summer, the county's air quality was so bad their monitors couldn't even measure it because their instruments max out at 1,000 micrograms.
COEFIELD: We pegged out 20 different times. So that's 20 hours that we don't know what the actual number was over a thousand.
SAKS: Researchers don't know a lot about that kind of extended smoke exposure. Most previous studies have focused on firefighters, indoor wood-burning stoves and urban air pollution. And it handed scientists a golden opportunity to learn more about the health effects. Chris Migliaccio is with the University of Montana's School of Pharmacy.
CHRIS MIGLIACCIO: Usually, these exposures are maybe a couple weeks at high levels. This was over a month at really unprecedented levels. We have no idea what the long-term effects are.
SAKS: Migliaccio, who's an immunologist, is part of a big team of UM researchers who are now trying to fill in those holes in knowledge. Working with the county health department, they've started tracking a group of Seeley Lake residents. They're documenting changes in their physical and mental health over time. He suspects they'll see more respiratory infections and residents with weaker immune systems.
MIGLIACCIO: I can't tell you you will be susceptible. You will get flu. But because of these exposures, you're probably at an increased risk. But we haven't done these studies. And that's something we want to follow with the Seeley Lake cohort.
SAKS: The biggest hurdle right now is funding. The researchers are applying for grants. They hope to track people for years to find out whether the health impacts of extended smoke exposure dissipate or linger on. For NPR News, I'm Nora Saks in Missoula, Mont.
SIMON: And that story, a part of a reporting partnership between NPR, Montana Public Radio and Kaiser Health News.