News Climate Wildfire smoke may ramp up toxic ozone production in cities A new study reveals what happens when urban pollution mixes with smoke’s chemical cocktail Smoke from wildfires blazing in California blankets the San Francisco skyline in an auburn haze. The mix of wildfire smoke and urban air pollution could increase ozone levels in the western United States, according to new research. Michael Short/Bloomberg Creative/Getty Images Plus Share this:EmailFacebookTwitterPinterestPocketRedditPrint By Ariana Remmel December 8, 2021 at 2:01 pm Wildfire smoke and urban air pollution bring out the worst in each other.