Carbon Monoxide (Help Files)

Information Supplied By The Ministry of Environment of Ontario

Carbon Monoxide (CO)

What is carbon monoxide?

CO is a colourless, odourless and tasteless but poisonous gas produced primarily by incomplete burning of fossil fuels.

What are the sources of CO?

The transportation sector accounts for 65 per cent of all CO emissions from human activity in Ontario as seen in the table and diagram below. A large part of the remainder comes from primary metal producers (24 per cent) and from fuel combustion in space heating and industrial processes (6 per cent).

Ontario Carbon Monoxide Emissions by Sector (Emissions From Human Activity, 2000 Estimates)
Pie Chart	Category	Percent
	Vehicles	45%
	Primary Metals	24%
	Other Transportation	20%
	Area Fuel Combustion	6%
	Other Processes	3%
	Miscellaneous Area Sources	2%

 

What are the effects of CO?

CO enters the blood stream and reduces oxygen delivery to the organs and tissues. People with heart disease are particularly sensitive. Exposure to high levels is linked with impairment of vision, work capacity, learning ability and performance of difficult tasks.

The following table shows the health effects of different Air Quality Index levels caused by carbon monoxide.

Health effects of different Air Quality Index (AQI) levels caused by carbon monoxide
Category	AQI	Carbon Monoxide (CO)
Very Good	0 - 15	No health effects are expected in healthy people.
Good	16 - 31	No health effects are expected in healthy people.
Moderate	32 - 49	Blood chemistry changes but no noticeable impairment.
Poor	50 - 99	Increased symptoms in smokers with heart disease.
Very Poor	100 or over	Increasing symptoms in non-smokers with heart disease; blurred vision; some clumsiness.