What Are the Major Air Pollutants?
Carbon Monoxide (CO) is an odorless, colorless gas. After being inhaled, CO molecules can enter the bloodstream, where they inhibit the delivery of oxygen throughout the body. Low concentrations can cause dizziness, headaches, and fatigue; high concentrations can be fatal.
CO is produced by the incomplete burning of carbon-based fuels, including gasoline, oil, and wood. It is also produced from incomplete combustion of natural and synthetic products, such as cigarette smoke. It can build up in high concentrations in enclosed areas such as garages, poorly ventilated tunnels, and even along roadsides in heavy traffic.
Carbon Dioxide (CO2) is the principal greenhouse gas emitted as a result of human activity (e.g., burning of coal, oil, and natural gas). CO2 can cause burns, frostbite, and blindness if an area is exposed to it in solid or liquid form. If inhaled, it can be toxic in high concentrations, causing an increase in the breathing rate, unconsciousness, and death.
Chlorofluorocarbons (CFCs) are chemicals used in great quantities in industry, for refrigeration and air conditioning, and in consumer products. CFCs, when released into the air, rise into the stratosphere (a layer of atmosphere high above the Earth). In the stratosphere, CFCs take part in chemical reactions that result in reduction of the stratospheric ozone layer, which protects the Earth's surface from the sun. Reducing the release of CFC emissions and eliminating the production and use of ozone-destroying chemicals is very important to the Earth's stratosphere.
Hazardous Air Pollutants (HAPs) are chemicals that cause serious health and environmental effects. Health effects include cancer, birth defects, nervous system problems, and death due to massive accidental releases, such as the disaster that occurred at a pesticide plant in Bhopal, India.
Hazardous air pollutants are released by sources such as chemical plants, dry cleaners, printing plants, and motor vehicles including cars, trucks, buses, planes.
Lead is a highly toxic metal that produces a range of adverse health effects particularly in young children. Lead can cause nervous system damage and digestive problems, and some lead-containing chemicals cause cancer. Lead can also harm wildlife.
Lead has been phased out of gasoline, which has considerably reduced the contamination of air by lead. However, lead can still be inhaled or ingested from other sources. The sources for lead include paint (for houses and cars), smelters, manufacture of lead batteries, fishing lures, certain parts of bullets, some ceramic ware, miniblinds, water pipes, and a few hair dye products.
Ozone (O3 is a gas that is a variety of oxygen. Oxygen consists of two oxygen atoms; ozone consists of three. Ozone in the upper atmosphere, where it occurs naturally in what is known as the ozone layer, shields the Earth from the sun's dangerous ultraviolet rays. However, at ground level where it is a pollutant with highly toxic effects, ozone damages human health, the environment, crops, and a wide range of natural and artificial materials. Ground-level ozone can irritate the respiratory tract, cause chest pain, persistent cough, an inability to take a deep breath, and an increased susceptibility to lung infection. Ozone can damage trees and plants and reduce visibility.
Ground-level ozone comes from the breakdown (oxidation) of volatile organic compounds found in solvents. It is also a product of reactions between chemicals that are produced by burning coal, gasoline, other fuels, and chemicals found in paints and hair sprays. Oxidation occurs readily during hot weather. Vehicles and industries are major sources of ground-level ozone.
Nitrogen Oxide (NOx) is a major contributor to smog and acid rain. Nitrogen oxides react with volatile organic compounds to form smog. In high doses, smog can harm humans by causing breathing difficulty for asthmatics, coughs in children, and general illness of the respiratory system. Acid rain can harm vegetation and run into lakes and rivers which changes the chemistry of the water, and makes it potentially uninhabitable for all but acid-tolerant bacteria.
Nitrogen oxides are produced from burning fuels, including gasoline and coal. (NOx) acid aerosols can reduce visibility.
Particulate Matter is any type of solid in the air in the form of smoke, dust, and vapors, which can remain suspended for extended periods. Aside from reducing visibility and soiling clothing, microscopic particles in the air can be breathed into lung tissue becoming lodged and causing increased respiratory disease and lung damage. Particulates are also the main source of haze, which reduces visibility.
Particulates are produced by many sources, including burning of diesel fuels by trucks and buses, fossil fuels, mixing and application of fertilizers and pesticides, road construction, industrial processes such as steel making, mining, agricultural burning, and operation of fireplaces and woodstoves.
Sulfur Dioxide (SO2) is an odorless gas at low concentrations, but can have a very strong smell at high concentrations. SO2 is a gas produced by burning coal, most notably in power plants. Some industrial processes, such as production of paper and smelting of metals, produce sulfur dioxide.
Like nitrogen oxides, SO2 is a major contributor to smog and acid rain. SO2 is closely related to sulfuric acid, a strong acid. It can harm vegetation and metals and can cause lung problems, including breathing problems and permanent damage to lungs.
Volatile Organic Compounds (VOCs) are organic chemicals. All organic compounds contain carbon, and organic chemicals are the basic chemicals found in all living things and in all products derived from living things. Many organic compounds we use do not occur in nature, but were synthesized by chemists in laboratories. Volatile chemicals produce vapors easily. At room temperature vapors readily escape from volatile liquid chemicals.
VOCs include gasoline, industrial chemicals such as benzene, solvents such as toluene and xylene, and perchloroethylene (principal dry cleaning solvent). VOCs are released from burning fuel, such as gasoline, wood, coal, natural gas and from solvents, paints, glues, and other products used at home or work. Vehicle emissions are an important source of VOCs. Many VOCs are hazardous air pollutants; for example, benzene causes cancer.
2007-03-14 07:24:53
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answer #1
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answered by Curly 4
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The nitrous oxide levels are now unacceptable. It's percentage in the atmosphere has risen by around 20% or more in the last decade. As it's also called laughing gas, i guess, we'll do a lot of giggling in the future. (just kidding!!) Nitrous oxide is prodused when we burn or produce various types of plastics, and styrofoams. Ther are probably other things that contribute as well, I'm sure.. Personally there are a lot of plastical "garbage" products out there we can do without. Look at all these kids toys, mass produced in China and other places. Most kids don't play with them very long, and very quickly lose interest in them. They are many of them , not worth the pollution making them emits. When I was little, we played better together as children. We had home made chess sets, and other games we made our selves. I think making the games, and playing games we made our selves, made playing them all the more fun. WE played cops and robberers, catch, tag, cowboys and indians, hide and go seek etc. And I think we had a lot more fun than kids today. My brother and I made a circus out of the hay barn, climbing on walls, and doing stunts. We did somersaults, and jumps, and all kinds of acrobatics. We were healthy , and in shape. At 42 I'm still more active, athletic, healthy, and flexible than people half my age. I don't feel a day over 20. I in fact do more, and have a more positiv and constructive outlook than I ever did. Kids nowadays, just play "killer computer games". It can't be good.
2007-03-14 07:29:01
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answer #2
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answered by irene k 2
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