Although air pollution might conjure images of urban smog and factory smoke stacks, its causes are many. Air pollutants come from both natural and human sources, and, unfortunately, we breathe them in every day. Recognizing the causes of air pollution can help prevent further damage to the environment.
Natural Sources
When air pollution is not caused by people or their activities, the source is natural, according to the National Park Service. Forest fires, volcanic eruptions, dust storms, wind erosion, pollen dispersal, evaporation of organic compounds, natural radioactivity and wild animals in their natural environments are examples of natural causes of air pollution. Each source emits particulate matter or gases into the atmosphere that contribute to air pollution.
Stationary Sources
While driving on a highway, there is a good chance you will see smoke coming out of factories, power plants, incinerators, petroleum refineries or industrial boilers. These are all examples of sources of stationary or industrial air pollution. The three major forces behind stationary air pollution are industrialization, population growth and globalization. Industry tends to burn fossil fuels such as coal, oil and gas to produce energy. In doing so, particulates such as sulfur dioxide, nitrogen oxides, heavy metals and volatile organic compounds are produced and emitted, which may contribute to air pollution.
Mobile Sources
For most people, a car is a major investment. But one disadvantage that usually comes along with it is air pollution. Motor vehicles are a major source of greenhouse gases, such as carbon dioxide, which may contribute to climate change, according to the Natural Resources Defense Council. Other types of on-road transportation include trucks, motorcycles and buses, which may produce pollutants such as carbon monoxide and sulfur dioxide. Off-road mobile sources such as lawn mowers, farm equipment, planes, trains and boats may also produce harmful gases.
Agricultural Sources
Many agricultural activities such as growing crops and raising animals can generate pollutants that may affect air quality, according to the National Park Service. Ammonia emissions from livestock waste; pesticide drift from spraying; and nitrous oxide emissions from the use of nitrogen fertilizer may all contribute to air pollution. When produced in large quantities, these pollutants have a negative effect on the respiratory system, skin and eyes. Swelling of the airways, pulmonary edema, cough, skin burns and glaucoma are among these effects.
Indoor Air Pollution
Air pollution is not restricted to the outdoors; it may occur in your own home or office. Sources of indoor air pollution include tobacco smoke, mold, pollen, radon, carbon monoxide, asbestos-containing insulation, aerosol cleaning products, central heating and cooling systems, and copying machines. Inadequate ventilation makes indoor air-quality problems worse, according to the Environmental Protection Agency. Usually poor indoor air quality only causes discomfort and irritation of the eyes, nose and throat, but some pollutants may cause diseases that manifest themselves later, such as cancer or respiratory conditions.
