What is Air Pollution?

There are many kinds of air pollution. The Environmental Protection Agency (EPA) calculates the Air Quality Index (AQI) for five major air pollutants regulated by the Clean Air Act: ground-level ozone, particle pollution, carbon monoxide, sulfur dioxide, and nitrogen dioxide. Ozone and particle pollution are two common pollutants found in many parts of the country. • Ozone is a colorless odorless gas. It’s the same kind of gas that’s found in the ozone layer. But in the ozone layer – high in the Earth’s stratosphere – ozone protects us from the sun. At ground level, where we live, ozone pollution is unhealthy to breathe. Ground-level ozone forms when pollutants from cars, trucks, power plants, industries, and some consumer products “cook” in the sun. Ozone usually peaks during the afternoon hours, when sunlight is the most intense.More about ozone. • Particle pollution, also called particulate matter, consists of microscopic particles in the air. It can be a problem in the winter or ...  more

Air pollution means the presence of one or more unwanted substances in air. Air pollutants have a negative impacts on humans, animals and plants, and on air quality. The most frequently present categories of air pollutants are sulphur oxides, nitrogen oxides, Volatile Organic Compounds (VOC) and small dust particles (aerosols).  more

Air is the ocean we breathe. Air supplies us with oxygen which is essential for our bodies to live. Air is 99.9% nitrogen, oxygen, water vapor and inert gases. Human activities can release substances into the air, some of which can cause problems for humans, plants, and animals. There are several main types of pollution and well-known effects of pollution which are commonly discussed. These include smog, acid rain, the greenhouse effect, and "holes" in the ozone layer. Each of these problems has serious implications for our health and well-being as well as for the whole environment. One type of air pollution is the release of particles into the air from burning fuel for energy. Diesel smoke is a good example of this particulate matter . The particles are very small pieces of matter measuring about 2.5 microns or about .0001 inches. This type of pollution is sometimes referred to as "black carbon" pollution. The exhaust from burning fuels in automobiles, homes, and industries is a ...  more

The air we breathe is made up of a mixture of gases and small particles. Pollutants in the air are chemicals or substances that are harmful to humans, other species, or ecosystems as a whole. These such pollutants can come from human (anthropogenic) sources, or from natural sources such as volcanos or dust storms. For more information visit the Weather Underground's main air pollution page.  more

Air pollution is the contamination of air by the discharge of harmful substances. Air pollution threatens the health of human beings and other living things on our planet. While often invisible, pollutants in the air create smog and acid rain, cause cancer or other serious health effects, diminish the protective ozone layer in the upper atmosphere, and contribute to the potential for world climate change. Since polluted air can move from one area or region to another, it has the potential to affect virtually all of us. Air pollution can cause health problems including burning eyes and nose, itchy irritated throat, respiratory problems, aggravate heart and respiratory problems. Above certain concentration and durations, certain air pollutants are extremely dangerous and can cause severe injury or death. Level, extent, and duration of exposure, age, individual susceptibility and other factors play a significant role in determining whether or not someone will experience pollution- ...  more

If there are other particles or gases in the air that are not part of its normal composition, we call this "air pollution" and the particles or gases are called "air pollutants." Very small amounts of certain air pollutants can cause serious health and environmental problems. We can see some air pollutants such as the reddish-brown haze in smog; however, other air pollutants, including some of the most dangerous, are invisible. Air pollution can be natural or human-made. Air pollution occurs naturally during volcano eruptions, forest fires, or dust storms. This has been an occasional problem for humans. However, during the past hundred years, air pollution created by humans has become a major, persistant problem. In California, our cities are among the smoggiest urban areas in the country.  more

Air pollution is made up of many kinds of gases, droplets and particles that reduce the quality of the air. Air can be polluted in both the city and the country. In the city, cars, buses and airplanes, as well as industry and construction may cause air pollution. In the country, dust from tractors plowing fields, trucks and cars driving on dirt or gravel roads, rock quarries and smoke from wood and crop fires may cause air pollution. Ground-level ozone is the major part of air pollution in most cities. Ground-level ozone is created when engine and fuel gases already released into the air interact when sunlight hits them. Ozone levels increase in cities when the air is still, the sun is bright and the temperature is warm. Ground-level ozone should not be confused with the "good" ozone that is miles up in the atmosphere and that protects us from the sun's harmful radiation.  more

Air pollution is caused by undesirable substances that enter the earth's atmosphere. It has become a big problem in today's societyespecially in larger cities.  more

There are many different types of air pollutants from a wide range of sources. The pollutants of greatest importance to health are the gases and particles that have been found to contribute to cardiovascular and respiratory disease. These pollutants are often lumped together under the term smog.  more

Air is primarily oxygen, nitrogen, and small amounts of other gases. Air pollution develops when human activity and natural sources affect this gaseous mix. Three main sources pollute these gases: • Sources that don t move: these include factories, refineries, and power plants. These are called point sources because they can be traced to a single point or location. • Sources that do move: these include cars, construction equipment, lawn mowers, all terrain vehicles, and boats. These are called mobile or nonpoint sources because the cannot be traced to a single point or location. • Sources that grow naturally: these include trees and grass and flowers. They are called biogenic sources.  more