Toronto sees worst air quality of major cities in the world as southern Ontario blanketed by smoke

Toronto has seen the worst air quality of major cities in the world on Wednesday as southern Ontario is blanketed by smoke from wildfires.

Global News meteorologist Anthony Farnell said the plume of smoke has descended on southern Ontario on the back side of an area of low pressure, extending into the U.S. Midwest and as far south as West Virginia.

“Air quality ranges from poor to dangerous and for a time on Wednesday, Toronto was the most polluted major city in the world using the AQI index,” he said.

“The number briefly touched 300 which is very unhealthy to breathe in, especially for an extended period of time.”

The poor air quality has prompted the City to make adjustments to some recreational programming.

Environment Canada has put a large portion of Ontario under a special air quality statement due to the smoke.

The weather agency said smoke plumes from forest fires over northeastern Ontario and Quebec have moved into the areas and the air quality has deteriorated.

“High levels of air pollution are expected to continue into today due to smoke from forest fires,” Environment Canada said early Wednesday.

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Areas under an air quality statement stretch along southern Ontario from Windsor and London, through the Greater Toronto Area to just outside of Ottawa. Areas north through Barrie, cottage country and North Bay are also covered.

The northwestern part of Ontario along the Manitoba border is also under an air quality advisory.

“Wildfire smoke can be harmful to everyone’s health even at low concentrations,” Environment Canada said.

“Air quality and visibility due to wildfire smoke can fluctuate over short distances and can vary considerably from hour to hour.”

As of Tuesday afternoon, there were 66 active fires in Northern Ontario, and as of this morning, 76 fires were burning across Quebec.

Conditions ‘slowly improving’

Farnell said conditions are “slowly improving” in southern Ontario as smoke shifts away and starts to disperse.

“As the wind direction changes in the coming days, periods of poor air quality will persist but not at the levels we are seeing on this Wednesday,” he said.

“When you have so much smoke in the weather pattern, even a wind shift just brings the smoke back into the area but from a different direction.”

Farnell said some rain has fallen around fires burning in northern Ontario and Quebec, but more is needed.

He said a “very warm period” is likely to happen through the first week of July which could bring an extreme fire risk and more smoke to the Great Lakes area.

“Right now we are at the mercy of the wind flow and as that changes, so do the concentrations of smoke,” Farnell said.

“The good news is that conditions are expected to be much better for the Canada.”

Here is a list of areas in Ontario under the special air quality statement:

• Simcoe – Delhi – Norfolk, Ont.
• Dunnville – Caledonia – Haldimand, Ont.
• Brantford – County of Brant, Ont.
• City of Toronto, Ont.
• Uxbridge – Beaverton – Northern Durham Region, Ont.
• Pickering – Oshawa – Southern Durham Region, Ont.
• Vaughan – Richmond Hill – Markham, Ont.
• Cobourg – Colborne – Western Northumberland County, Ont.
• Fenelon Falls – Balsam Lake Park – Northern Kawartha Lakes, Ont.
• Apsley – Woodview – Northern Peterborough County, Ont.
• Lindsay – Southern Kawartha Lakes, Ont.
• Peterborough City – Lakefield – Southern Peterborough County, Ont.
• City of Hamilton, Ont.
• Mississauga – Brampton, Ont.
• Halton Hills – Milton, Ont.
• Burlington – Oakville, Ont.
• St. Catharines – Grimsby – Northern Niagara Region, Ont.
• Niagara Falls – Welland – Southern Niagara Region, Ont.

— with a file from The Canadian Press