Toronto West, Ontario PM2.5 (fine particulate matter) AQI is 13 - Toronto West, Ontario PM10 (respirable particulate matter) AQI is n/a - Toronto West, Ontario NO2 (nitrogen dioxide) AQI is 3 - Toronto West, Ontario SO2 (sulfur dioxide) AQI is n/a - Toronto West, Ontario O3 (ozone) AQI is 16 - Toronto West, Ontario CO (carbon monoxide) AQI is 2 -