As wildfires multiply, a new era of air pollution

Washington (AFP) - From Quebec to British Columbia to Hawaii, North America is facing an extraordinary wildfire season -- and regions both near and far have found themselves increasingly blighted by smoke exposure. Here's what you should know about air pollution from these blazes. What we knowOne of the defining aspects of smoke from wildfires is "particulate matter" -- toxins that, in their numbers, can make smoke visible. Particulate matter of 2.5 micron diameter, PM2.5, is "particularly dangerous for human health and emitted in really large quantities," Rebecca Hornbrook, an atmospheric che...