Air quality advisories have now been issued for Wednesday in Ontario, Quebec, and Western New York, conditions the state has not experienced in more than 20 years.
The smoke can be seen and smelled in Toronto and is likely to get worse before the week is over.
Environment Canada says the air quality advisory will remain in the Greater Toronto Area because of high levels of smoke pollution.
“We’ll certainly see the situation in the GTA. And it will be unhealthy and it will linger for as long as the weather stays stale,” said Dave Phillips, senior climatologist with Environment Canada.
The warning is especially acute for those at high risk, said Martha Robinson of Ottawa Public Health.
“Older adults, people with pre-existing illnesses like heart and lung, diabetes, people with cancer.”
As of Tuesday, there were about 160 forest fires burning in Quebec and nearly 50 in northern Ontario.
Federal officials say wildfires burning in British Columbia and Nova Scotia are likely some of the worst ever seen in Canada, and they say the forecast for the next few months suggests the potential for continued above-average fire activity this year.
