Toronto Air Quality

PM2.5 – Fine particulate matter less than 2.5 micrometers in diameter. These tiny particles can penetrate deep into the lungs and even enter the bloodstream.

PM10 – Inhalable particles, with diameters generally 10 micrometers and smaller. These can deposit in the airways.

O3 (Ozone) – A gas that occurs both in the Earth’s upper atmosphere and at ground level. Ground-level ozone can harm lung function and irritate the respiratory system.

NO2 (Nitrogen Dioxide) – A highly reactive gas formed when fuel is burned at high temperatures. It can cause inflammation of the airways and reduced lung function.

SO2 (Sulfur Dioxide) – A gas produced from burning fossil fuels containing sulfur. It can cause respiratory issues and make breathing difficult.

CO (Carbon Monoxide) – A colorless, odorless gas that can be harmful when inhaled in large amounts. It reduces oxygen delivery to the body’s organs.