Weekend may see relief from wildfires' pollution

As smoke and haze from Canada's wildfires swept over the Northeast for a third day Thursday, and spread to the Midwest and the South, there was little that the millions of people engulfed by it could do but ask when it will end. Not very soon, said forecasters.

The air pollution will possibly persist until the weekend, according to forecasters. Lee Hendricks, a meteorologist for the National Weather Service in Pittsburgh, said a high-pressure system in the West was helping to push smoke south into the US. Until the current weather pattern shifts, he said, "nothing is going to significantly improve".

There was no end in sight for the wildfires, especially the approximately 150 fires in the eastern province of Quebec that forced more than 11,000 thousand people from their homes. Environment Canada said conditions were worsening in Toronto on Thursday, as more smoke poured in. About 3.8 million hectares (9.4 million acres) have burned throughout the provinces.

Data from the US Environmental Protection Agency's Air Quality Index (AQI) shows that cities in North America had the worst air quality in the world on Thursday morning.

Conditions in parts of the Northeast on Thursday were better than Wednesday, the worst day on record in the US for wildfire smoke since 2006, according to research from Stanford University. Scientists deemed the air to be unhealthy for all age groups.

More than 40 million people in the US live in areas that have air quality rated unhealthy or worse, according to AirNow, a government tracking site.

The smoke-filled skies prompted a call from UN Secretary General António Guterres to tackle climate change. The world needs to urgently reduce wildfire risk and make peace with nature, he said. US President Joe Biden described the fires as a "stark reminder of the impacts of climate change." Biden said he spoke to Canadian Prime Minister Justin Trudeau on Thursday about the fires. The US has deployed 600 firefighters to Canada

In the capitol, the White House's planned pride celebrations were canceled. The National Zoo was also closed, with its animals, including three giant pandas, taken indoors to shelter.

In New York, the air pollution has led to canceled outdoor sporting events, shut down Broadway plays and the Bronx and Central Park zoos, delayed thousands of airplane flights, sparked a resurgence in wearing masks and raised concerns about the health effects of prolonged exposure to such bad air.

The city's public hospital system reported a minor increase in patients with respiratory ailments because of the smoke-filled air.

Those who went outdoors put on masks; those indoors closed windows and turned on air conditioning if they had it.

New York Governor Kathy Hochul said that one million N95-style face masks would be made available to the public. The CEO of Ambrust American, a mask manufacturer in Elgin, Texas, said sales of one N95 mask model jumped 1,600 percent between Tuesday and Wednesday.

Agencies contributed to this story.