Wildfire smoke in US exposes millions to hazardous pollution

On a clear day is the skyline behind Crissy Field in San Francisco on Oct. 11, 2020. Wildfires that scorched huge swaths of the West Coast churned out massive plumes of choking smoke that blanketed millions of people with hazardous pollution that spiked emergency room visits and that experts say could continue generating health problems for years. An Associated Press analysis of air quality data shows 5.2 million people in five states were hit with hazardous levels of pollution for at least a day.