Nitrogen Dioxide

Ozone

Carbon Monoxide

Sulfur Dioxide

Particulate Matter

Lead
 

Carbon Monoxide - CO
Carbon monoxide is an odorless, poisonous, invisible gas released into the air primarily by engines that burn fossil fuels. When these engines don't completely burn the carbon in the fuel, they emit carbon monoxide.

Where
More than 80% of carbon monoxide is produced by motor vehicles, especially during cold starts, idling, and traffic congestion. Much less is emitted from wood and agricultural burning, small engines, and some industrial processes. High concentrations of carbon monoxide are found in relatively closed spaces like parking garages, poorly ventilated tunnels, or along roadsides during heavy traffic.

Effects
Carbon monoxide enters the bloodstream, replacing oxygen carried by the red blood cells and reducing our body's ability to deliver oxygen to the organs and tissues. Lack of oxygen affects the brain, impairing visual perception, manual dexterity and the ability to think. Extremely high levels of carbon monoxide in closed places (like a garage) are very dangerous, and can cause death by heart failure or asphyxiation.

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