Air quality reaches hazardous levels in parts of the US and Canada amid Canadian wildfires
Air quality indexes above 300, with some cities exceeding 500, have prompted health officials to warn against outdoor exposure and highlight increased risks of respiratory and cardiovascular problems.
Smoke from wildfires in Canada has pushed air quality to hazardous levels in several U.S. and Canadian cities, with the Air Quality Index (AQI) surpassing 500 in Toledo, Milwaukee and Detroit on Thursday. An AQI above 300 is classified as hazardous, indicating that outdoor activity should be avoided.
"Nobody should spend time outside," said Laura Corlin, an associate professor of public health and community medicine at Tufts University School of Medicine. "The level is literally dangerous for everybody."
Public health experts note that such extreme pollution levels are rare in North America, limiting the amount of existing research on health impacts at these concentrations. Dr. Alexander Rabin, a pulmonologist at Michigan Medicine, said the particle pollution is "astronomically high" and linked to a range of symptoms, including wheezing, coughing, eye irritation, sore throat, runny nose, headaches and fatigue. People with asthma, chronic lung disease, heart conditions, children, pregnant women and older adults are considered most vulnerable.
Health officials advise anyone experiencing chest pain or breathing difficulties to seek immediate medical care. Emergency departments, such as the Veterans Affairs hospital in Ann Arbor, Michigan, have reported an uptick in patients with exacerbated chronic obstructive pulmonary disease and other lung conditions.
The long-term effects of prolonged exposure to such severe smoke are still uncertain, and experts do not know when the smoke will dissipate.
"Who knows how long this is going to go on for? This could linger for quite some time," Dr. Rabin said.