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However, while the controls have reduced the amount of pollution from each vehicle, the number of vehicles on Vermont roads and the number of miles they travel has increased dramatically. Motor vehicles now travel over 6 billion miles annually in Vermont; double the amount traveled in 1972. The increase in vehicles and road miles is a trend that is expected to continue or the foreseeable future.
Topics
What pollutants come out of vehicles?
What are the human health effects and environmental consequences of motor vehicle pollution?
How do roads contribute to pollution?
What pollutants come out of vehicles?
The major car pollutants are carbon monoxide, hydrocarbons, nitrous oxides, carbon dioxide, and particulates. Most car pollutants come from the exhaust but brake pads, tires, oil, grease, anti-freeze, hydraulic fluids, and cleaning agents also contribute pollutants to the environment.
| Ozone (ground level) |
| Sources: |
Produced by chemical reactions among pollutants, released mainly by motor vehicles (nitrogen oxides and volatile hydrocarbons). |
| Environmental impacts: |
A strong oxidant gas that damages animal respiratory systems, plant leaf cells, reducing photosynthesis. |
| Human health concerns: |
A respiratory irritant causing damage to the lungs, reducing lung capacity and aggravation respiratory problems, especially in the elderly, the very young, and the asthmatic. |
| EPA maximum allowable level: |
An average of 80 ppm (parts per million) for any 8 hour period. It is important to note that the current guidelines have been found to be inadequate in protecting human health and are in the process of being revised. |
| Particulate Matter |
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There are three size classes of particles in the air that are regulated: fine (less than 2.5 micrometers [um] in diameter); coarse (less than 10 um in diameter); and total (all particles up to about 50 um). While the regulations govern only the amount of these particles in our air, their composition (which may include toxic compounds as well as dust, salts, and soot) is also a concern. |
| Sources: |
Industrial and vehicle combustion, woodsmoke, refining, industrial and vehicle abrasion, road dust, quarrying, milling, large scale transfer of dusty materials. |
| Environmental impacts: |
Visibility reduction, respiratory irritant, and nuisance. |
| Human health concerns: |
Fine particles are a respiratory irritant, causing lung damage, bronchitis, and asthma; all particles can be somewhat irritating, especially to those with respiratory problems. |
| EPA maximum allowable level: |
Fine (PM 2.5) 15 micrograms per cubic meter (ug/m3 ) annual average and 65 ug/m3 for any 24 hour period. Coarse (PM 10) 50 ug/m3 annual average and 150 ug/m3 for any 24 hour period. Total (TSP) |
| Benzene (see indicators section) |
| Sources: |
Vehicle exhaust, vapors at gas pump, fossil fuel emissions and wood stove combustion. |
| Human health concerns: |
Long-term exposure to elevated levels may damage tissues, cause anemia, and leukemia. |
| State maximum allowable level: |
0.12 ug/m3 |
| 1994 annual average in Burlington: |
2.62 ug/m3 |
| 1,3,-Butadiene (see indicators section) |
| Sources: |
Vehicle exhaust, and the emissions from wood burning and waste incinerators. |
| Human health concerns: |
Irritant to eyes, nose and throat; exposure to high levels can damage the central nervous system, cause blurred vision, nausea, fatigue, decrease blood pressure and pulse rate. Increased incidences of heart disease, lung disease, and cancer have been noted in workers who have inhaled butadiene for long periods of time. |
| State maximum allowable level: |
0.035 ug/m3 |
| 1994 annual average in Burlington: |
0.64 ug/m3 |
What are the human health effects and environmental consequences of motor vehicle pollution?
Motor vehicles emit toxic and carcinogenic compounds that are known to cause cancer in humans. Hydrocarbons and nitrogen oxides contribute to smog, which damages lung tissues and aggravates respiratory disease. Smog can also inhibit plant growth and damage crops and forests. Motor vehicle pollution also contributes to the formation of acid rain and global warming.
Air pollution accounts for about 6 percent of deaths each year in Austria, France, and Switzerland, according to a study published in the Lancet medical journal. The study found that half of the those deaths can be attributed to pollution from vehicles. The researchers also calculated that the health cost of vehicle pollution in the three countries totaled 1.7 percent of the gross domestic product. (Related articles can be found in the London Times and the Los Angeles Times for 09.01.2000)
For further information on the effects car pollutants have on the environment and humans see the EPA website: http://www.epa.gov/OWOW/NPS/roads.html
How do roads contribute to pollution?
Roads are a large contributor to nonpoint pollution in Lake Champlain. Water can not penetrate the surface of a paved road or parking lot and instead travels along the surface as runoff. After it rains or the snow melts, urban runoff travels over the streets of Burlington picking up a variety of pollutants until it finally reaches Lake Champlain. These pollutants include sediments, heavy metals, oil, grease, debris, fertilizer, pesticides, herbicides, road salts, and pet wastes. Particulate matter and heavy metals come from exhaust, break pads, tire and asphalt ware, drips of oil, grease, anti-freeze, hydraulic fluids, and cleaning agents. Urban runoff negatively impacts the environment by harming aquatic plant and animal life (limiting growth, toxicity, fish kills), degrading water quality, contaminating ground water, and contributing to eutrophication.
See the USGS's monitoring of Englesby Brook and also water > issues > urban runoff.
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