What's Going On Up There? and What's It Doing Down Here?
Air pollution is one of those complicated subjects where each factor is related to the other in a busy interdependent cycle of air pollution, atmospheric change, and natural balances.
Particulate matter (PM) is both plain old dust, from roads, fields or wood, and particles formed through chemical actions. Other air pollutants form PM — sulphur dioxide (SOx), nitrogen dioxide (NOx), volatile organic compounds (VOCs), and ammonia.
The burning of carbon-based material releases vast quantities of carbon dioxide implicated in global warming – also called climate change, because we're not quite sure what the effects will be.
But in the end, it is deceptively simple. Burn stuff — wood, natural gas, gasoline, oil, coal — you may produce energy, but the chemical results go into the air, and, presto! air pollution. Burn carbon-based fuels and carbon dioxide is released to the atmosphere, forming a blanket which absorbs the sun's heat, creating the "GreenHouse Effect." The dire consequences predicted from fast human-induced warming of the planet range from drought and forest die-off to tidal flooding of most of the world's major cities, and some lovely little Pacific islands.
Although the atmosphere is a big place, humans have been so busy burning coal, oil and gas since the industrial revolution that we have actually physically changed the make up of the atmosphere. The concentration of carbon dioxide (CO2) in the atmosphere has increased from about 280 ppmv (parts per million by volume) before the industrial revolution, to 358 ppmv in 1994, and it is still on the rise. Other man-made chemicals have shown an even greater increase. Whatever the eventual outcome of climate change, it does defy common sense to suggest that changing the composition of the atmosphere won't have any effect on Spaceship Earth.
Certainly levels of childhood and adult asthma are on the rise. And certainly citizens are antagonised by air pollution like never before, from the CHOKED (Citizens Health Opposition to Known Emission Dangers) communities in the interior of BC , which organize for the long overdue shutdown of the beehive (wood waste) burners, to OntAIRio, a clean air network trying to convert coal-burning power plants to less polluting natural gas turbines.
Although it seems like air pollution has been with us forever, from the smoky wood fire to the industrial smogs of the nineteenth century, scientists say it has been harming us just as long. During the scientific assessment for the new Canada Wide Standards, agreed to by consensus with all the provinces, federal scientists found no evidence of any safe level of exposure to fine Particulate Matter or ozone.
Health Impacts of Common Air Pollutants
Ammonia: Precursor to fine particulate formation. Irritant.
Carbon Monoxide: Human visual impact at 50 ppm for one hour, death at more than 750 ppm, vegetation impact at higher levels.
Carbon Dioxide: Greenhouse gas.
Chloroform: Recognized carcinogen, suspected respiratory, cardiovascular or blood, liver and kidney toxicant, endocrine and neurological disruptor.
Methanol: Accepted by the US EPA as a surrogate monitoring measurement for a wide range of the Hazardous Air Pollutants (chlorinated compounds). Suspected developmental toxicant, neurotoxin, gastrointestinal or liver toxicant
Nitrogen Oxides (NOx): NO2 is acute respiratory irritant at 1 ppm for 15 minutes. Harmful air contaminant, precursor to smog, ground level ozone, fine particulate and acid rain. Harmful to humans, vegetation growth and health.
Sulphur Oxides (SO2, SO3 and solid sulphates): Irritating to eyes and respiratory system at 5 ppm for 10 minutes. SOx is a precursor to fine Particulate Matter formation. Sulphuric acid is implicated in bronchitis, emphysema, eye, nose, and stomach irritation, and possible lung cancer in exposed workers.
The Canadian Council of Ministers of Environment set goals, or Canada Wide Standards, for exposure in ambient air of 65 ppb ozone averaged over 8 hours, and 30 micrograms of PM 2.5 (particulate matter smaller than 10 microns) averaged over 24 hours, to be achieved by 2010. British Columbia has set a new air quality objective of 25 ug/m3 for PM 2.5, but most communities exceed these levels at least 5% of the time.
Environmentalists call these consensus documents Canada-Wide Suggestions, because all environmental actions are passed through the filters of affordability, economic feasibility, and provincial government action. Since changes to products and industrial systems will take new investment, the choked citizens of Canada had better not hold their breath waiting for the air to change.
Air Quality Index
Because air pollution is such a complicated problem, governments use the Air Quality Index to inform us. This index compares air quality to a range of measurements from continuous monitoring stations, with breakpoints of Good, Fair and Poor. The BC and Federal system is similar, measuring Sulphur Dioxide, Carbon monoxide, Nitrogen Dioxide, Ozone, and Fine Particulate against standards for Good, Fair, Poor and Deplorable.
Sources of Carbon Dioxide (CO2) Emissions in British Columbia, 1989
* Greenhouse Gas Inventory and Management Options: A Summary Report for British Columbia