This story appears in the April 2021 issue of National Geographic magazine.
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An urgent question hangs over catastrophic wildfires: What’s in that toxic smoke?
Scientists are rushing to learn more about those dangerous swirls of gases and particulate matter—and how they threaten our health.
The Angeles National Forest, in Southern California, is engulfed in smoke and flames during last year’s record-breaking wildfire season. The Bobcat Fire, as this one was called, burned more than 115,000 acres. It was one of scores that blew smoke pollution across the western states and beyond—visible as far away as Washington, D.C.
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