According to the air quality measuring website AQI. which claims to measure the "100 Most Polluted Cities in The World" in real time, North Bay had the second worst pollution ranking on Earth yesterday.
North Bay still ranks in the Top 10 most polluted cities in the world as of this morning (Monday). Sudbury is ninth.
Air quality in the area is presently at 287, which is considered unhealthy.
Sault Ste. Marie didn't make the Top 100, according to AQI, but Environment Canada has maintained its special air quality statement.
Very high levels of air pollution have developed due to smoke from forest fires. Smoke plumes from forest fires in Quebec and northeastern Ontario will continue to affect the area, resulting in deteriorated air quality.
Conditions are expected to improve for some areas Tuesday night or Wednesday.