Environment Canada has issued a smog warning for several regions of Quebec along the St. Lawrence River, including Montreal and Quebec.
The federal agency says it expects poor air quality in the affected areas on Saturday because of the high concentrations of pollutants in the air.
The warning also applies in the sectors along the St. Lawrence River from the southern borders of the province to Montmagny, in Chaudière-Appalaches.
It also covers parts of Beauce and Gatineau.
Environment Canada says Montrealers should stop using wood stoves and fireplaces until the warning is lifted. A Montreal bylaw prohibits the use of wood-burning appliances when smog warnings are in effect.
The city says wood-burning appliances are a major contributor to winter smog.
The Quebec Ministry of the Environment said that as of noon on Saturday, air quality was poor in Laval, near Montreal, as well as part of Quebec City. The City of Montreal said the air quality was poor in the eastern part of the island.
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