(BOULDER, CO) Wildfire smoke has been pouring across the northern U.S. from fires in Canada and Minnesota, turning skies an eerie shade of orange in several states in July 2026. In the West, smoke has also been spreading into communities in Colorado and neighboring states as more wildfires burn in hot, dry conditions.
University of Colorado environmental health researcher Colleen Reid explains what’s in that smoke and why breathing it is a health concern everyone should be aware of.
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