WATERLOO -- Environment Canada has issued a special air quality statement for Waterloo Region and the rest of southwestern Ontario.

The special statement, issued around 5:55 p.m. Monday, says high levels of air pollution due to smoke from ongoing forest fires are possible.

The smoke is causing poor air quality and reducing visibility, according to the statement.

"Individuals may experience symptoms such as increased coughing, throat irritation, headaches or shortness of breath. Children, seniors, and those with cardiovascular or lung disease, such as asthma, are especially at risk," the special air quality statement reads.

Environment Canada says smoke from active forest fires in northwestern Ontario has moved over southern Ontario, with hazy conditions reported at several stations.

Officials say conditions are expected to improve Tuesday with the passage of a cold front.