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Air Exceedances by Station


This report provides an annual trend in the following ten pollutants:

Ozone (or O3): Ozone is a light blue gas with sharp odour found in the upper atmosphere and near the ground. Unlike other pollutants, ozone is not directly emitted to the atmosphere. It is a secondary pollutant formed by a complex reaction with "primary" pollutants. Motor vehicles are a significant source of these primary pollutants. Ground-level ozone is a component of smog and can be harmful to human health and vegetation.

Total Volatile Organic Compounds (or VOCs): VOCs include a large group of chemicals containing carbon and hydrogen atoms that can react quickly to form other chemicals in the atmosphere. The major sources of VOCs are automobile emissions, gasoline marketing and storage tanks, petroleum and chemical industries, natural gas combustion and natural emissions from vegetation (e.g., forests). VOCs are important because they can react to form ozone and smog and be toxic to humans, animals or vegetation.

Benzene (C6H6): Benzene is a VOC and is a known human carcinogen (cancer-causing substance). Motor vehicle emissions are the main source in Alberta, followed by industrial emissions and other combustion sources. Benzene can be harmful to the environment and prolonged exposure can cause serious health effects in humans.

Oxides of Nitrogen (or NOx) – NO, NO2 and other NOx: Nitrogen oxides (or NOx) are a family of gases that are formed through high temperature burning of natural gas, coal, oil and gasoline. The largest urban source of NOx is emissions from motor vehicles. Other sources include oil and gas industries, power plants and forest fires. NOx contributes to the formation of ground-level ozone and acid deposition or acid rain. Exposure can cause lung irritation and lower resistance to respiratory infections.

Carbon Monoxide (CO): Carbon monoxide is a colourless, odourless gas that reduces the ability of blood to absorb and deliver oxygen to cells in the body. It is formed when carbon-based fuels, such as gasoline, natural gas and wood, are incompletely burned. The major source of carbon monoxide in urban areas is exhaust from motor vehicles.

Fine Particulate Matter (PM2.5): Fine particulates are tiny particles that are smaller than 2.5 microns. To give an idea of how small this is, a strand of human hair is about 70 microns in width. Smaller particles have the ability to travel deeper into the lungs where they may cause permanent lung damage. Sources include soil, roads, agricultural dust, vehicles, industrial emissions, smoke from forest fires, cigarettes, household fireplaces and barbecues. Particulates may cause human health problems and also play a role in the production of smog, acid deposition and reduced visibility.

Sulphur Dioxide (SO2): SO2 is a compound formed when fossil fuels, such as coal and natural gas, are burned. Sulphur dioxide can cause health effects and is a key contributor to acid deposition, including acid rain. It is also contributes to particulate matter. Fossil fuel combustion - which produces sulphur dioxide - is used to generate electricity, heat homes and power vehicles. Major sources of SO2 in Alberta include, natural gas processing plants, oil sands facilities and power plants.

Hydrogen sulphide (H2S): H2S is a gas with a "rotten egg" smell. Industrial emissions are the main source of hydrogen sulphide, including emissions from petroleum refineries, natural gas plants, petrochemical plants and oil sands plants. Hydrogen sulphide generally presents an odor problem, but at high concentrations can it cause health effects in humans and be toxic to animals, birds and aquatic environments.

Total Reduced Sulphur Compounds (or TRS): Total reduced sulphur (TRS) includes hydrogen sulphide, mercaptans, dimethyl sulphide, dimethyl disulphide and other sulphur compounds. Like H2S, these compounds present an odour problem. Industrial sources of TRS include fugitive emissions (leakages) from petroleum refineries, tank farms for unrefined petroleum products, natural gas plants and petrochemical plants.

Polycyclic Aromatic Hydrocarbons (or PAHs): PAHs are a class of chemicals that are formed during the incomplete combustion of gasoline, diesel, oil, coal, wood, garbage or other organic substances. Tobacco smoke and charbroiled meats are common sources of PAHs. Other outdoor sources of PAHs include vehicle exhaust emissions, wood smoke from fireplaces, smoke from forest fires and industrial facilities. There are more than 100 different PAHs with varying levels of toxicity. People can be exposed to PAHs through breathing, eating or drinking substances that contain PAHs, or through skin contact.


Posted Date: Jun 17, 2010 Source:
Alberta Environmental Monitoring, Evaluation and Reporting Agency
Date Range: Aug 8, 1986 - Present Location:   Lower Athabasca, Lower Peace
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Usage Considerations

In many cases, objectives are established for more than one duration – e.g. the site should not emit an average of more than 15,000 ug/m3 of substance A in one hour, and should not emit more than an average of 6,000 ug/m3 of the same substance over an 8 hour period.

NB: Data was collected by the Alberta Environmental Monitoring, Evaluation and Reporting Agency (AEMERA) until June 30, 2016, at which point AEMERA was dissolved and the Environmental Monitoring and Science Division of Alberta Environment and Parks was created.