https://apnews.com/article/canada-science-health-environment-and-nature-coronavirus-pandemic-22599eded88b808881b86c22505136a5

"The combined plume from Canada and the U.S. largely passed over parts of the Midwest this week before settling to ground level across an area that stretches from Ohio northeast to New England and south to the Carolinas, air pollution data shows. Health effects can occur thousands of miles from the flames. The smoke loses its tell-tale odor but remains a potential hazard even when it drifts that far, said Jeff Pierce, an atmospheric scientist at Colorado State University. 'It’s certainly unhealthy,” Pierce said of the air along the East Coast in recent days. “If you have asthma or any sort of respiratory condition, you want to be thinking about changing your plans if you’re going to be outside.'”