High pollution levels in the Edmonton area have prompted a special air quality advisory statement from Environment Canada that's expected to remain in effect until Monday.

Pollution is trapped in the area due to an atmospheric inversion, according to Environment Canada. This happens when the atmosphere becomes warmer as the altitude increases, and can trap pollution below.

The Air Quality Health Index was a level seven, or high risk, as of Sunday morning.

The advisory is in effect for Edmonton, St. Albert, Fort Saskatchewan, Vegreville, Redwater and Smoky Lake.

Residents could experience symptoms like coughing, throat irritation, headaches or shortness of breath. Most at risk are children, seniors, and people with cardiovascular or lung diseases.

The air quality is expected to improve on Monday as winds increase.