Wildfire smoke from Ontario has severely degraded air quality across the northeastern United States. Chicago recorded "Very Unhealthy" levels of fine particulate pollution on Wednesday. Toronto briefly ranked as the world's most polluted major city while New York issued alerts. Health advisories urge residents to reduce strenuous outdoor activities as smoke spreads. Authorities continue monitoring air quality as wildfire smoke shifts with weather patterns.

New York City has been dealing with a "Code Red" due to the heat and air quality advisories from Canadian wildfire smoke days before the Spain-Argentina World Cup final.

Air quality alerts have been issued from Wisconsin and Michigan through New York and Massachusetts due to Canadian wildfire smoke.

Chicago's air quality has become hazardous due to Canadian wildfire smoke. This pollution has affected over 125 million people across the Midwest and Northeast. Health officials…