The Illinois EPA declared an Air Pollution Action Day in the Chicago metro area. See today's air quality index forecast for Illinois.

The Air Quality Index (AQI) is a national system developed by the U.S. Environmental Protection Agency (EPA) to translate various air pollutant concentrations into a single, easy-to-understand number.

An Air Quality Alert has been issued for parts of northern New York and Vermont today because of Canadian wildfire smoke.

Much of Central Canada, Manitoba and Saskatchewan were placed under special air quality statements or warnings on Monday due ...

The only cities with worse air quality than Montreal this morning were Kinshasa (DR Congo), Manama (Bahrain), Santiago (Chile ...