Environment Canada issued an alert on Monday to parts of the Greater Toronto Area “due to the possibility of deteriorating air quality.”
In the alert, the agency initially said this was “as a result of fireworks for Diwali.”
However, by Monday afternoon, the weather agency updated its statement without mention of Diwali, but maintained its concerns about air quality.
Environment Canada did not respond immediately to questions about why it had removed the reference.
The weather agency said high levels of air pollution are expected Monday evening into the overnight hours on Tuesday.
“Light winds and stagnating weather conditions are expected to cause increasing levels of air pollution,” Environment Canada said. “Air quality may deteriorate if the smoke from fireworks remains at or descends to ground level.”
The special weather statement is in effect for Toronto, Brampton, Mississauga as well as York and Durham regions.
“If you or those in your care are exposed to firework smoke, especially those who are particularly sensitive to smoke, consider taking extra precautions to reduce your exposure.”
Environment Canada said some may experience increased coughing, throat irritation, headaches or shortness of breath. Children, seniors and those with asthma are more at risk, they added.
-with files from The Canadian Press