Urban wildfires bring lingering worries about what’s in the ash and air


For weeks, smoky, unhealthy air from large wildfires has plagued much of the West Coast and beyond. What’s the public health impact of an increase of urban wildfires, in which homes and other structures burn? Special correspondent Cat Wise meets some of the researchers studying the risks for people from smoke and ash.

  • William Brangham:

    Now to another story about extreme weather and its impact.

    Wildfires have plagued Northern California and the Pacific Northwest this year. In California alone, some 6,400 fires burned nearly one-and-a-half million acres.

    Most destroy wildlands, but, as special correspondent Cat Wise reports, some urban areas are increasingly under threat. And it’s not just a danger from fire. Researchers are trying to understand the risks from all that smoke and ash.

  • Cat Wise:

    Last October, this was Santa Rosa, California’s Coffey Park neighborhood. Today, nearly a year later, it looks like this. Crews of busy construction workers are rebuilding hundreds of homes. Nail by nail, communities around the region are rising from the ash.

    But there are questions about what was in that ash and in the air above that could impact residents long after the rebuilding is done.

    On a recent morning, air pollution scientist Keith Bein drove through the streets of Coffey Park hauling two small electric vehicles and some equipment he hopes will help him eventually answer some of those questions.

    These Mercedes smart E.V.s are a key part of the prototype system Bein has designed to get better air quality information to the public in the aftermath of a wildfire. Think storm chaser, but instead of looking for tornadoes, he’s chasing wildfire smoke.

  • Keith Bein:

    Well, I call this the rapid-response mobile research unit. We can deploy this thing at the drop of a hat, and we can go anywhere we want to. There doesn’t have to be power.

  • Cat Wise:

    Each vehicle can run his sophisticated air sampling equipment for 18 hours.

  • Keith Bein:

    I’m going to flip a switch to turn it on. There it goes.

  • Cat Wise:

    Bein is part of a University of California at Davis collaborative research project looking at the short-term and possible long-term health impacts from the North Bay wildfires.

    The study is funded by the National Institutes of Health, which is also a “NewsHour” funder.

    After spending several days sampling Redding in the Carr Fire, he brought his mobile lab to Santa Rosa to see what might still be lingering in the air.

  • Keith Bein:

    The wildfires that I sampled from Napa and Sonoma were this off-white, tannish color that I had never, ever seen before. When you have new situations like this, these urban wildfires, now you’re just — any consumer product, cars, paint, cleaners, construction materials, you name it, it’s all going up in flames.

    Then all of those emissions are going to be very different both chemically and most likely toxicologically, compared to what we normally study as very isolated wildfires.

    Learn more here.