Primary air pollutants include carbon monoxide from the burning of organic materials, hydrocarbons from automobile exhaust, particulates from industrial plants, sulfur dioxide from electric generation facilities using high sulfur fuels, and oxides of nitrogen from internal combustion engine exhaust.
The 6 criteria air pollutants and their primary sources are:
carbon monoxide—burning of fossil fuels (Automobiles are the primary source.);
nitrogen dioxide—secondary air pollutant formed from nitrogen monoxide released from automobiles;
sulfur dioxide—burning of sulfur-containing fossil fuels, primarily coal in power plants;
volatile organic compounds (hydrocarbons)—evaporation or incomplete burning of hydrocarbons, primarily automobiles;
ozone—a secondary air pollutant formed by the interaction of volatile organic carbons and nitrogen oxides released from cars;
lead—primary sources today are industrial processes (Formerly, leaded gasoline was a primary source.).
Secondary air pollutants are compounds that result from the interaction of various primary air pollutants. Photochemical smog forms when hydrocarbons and oxides of nitrogen are trapped by thermal inversion and react with ultraviolet light.
Health effects of air pollution include bronchial inflammation, allergic reactions, irritation of the mucous membranes of the eyes and nose, and asthmatic problems.
Increased pollution in industrialized urban areas is due to the large number of industrial plants, the large concentration of automobile traffic in these areas, and temperature inversions that cause large amounts of pollution to accumulate.
Photochemical smog is a secondary pollutant caused by the interaction of nitrogen oxide, nitrogen dioxide, and hydrocarbons with ultraviolet light. It is caused by exhaust from internal combustion engines and is intensified in valleys that produce temperature inversions.
Air pollution can be controlled by building taller smokestacks, installing emission control devises in automobiles, and legislating to control or eliminate open burning.
Acid rain is the deposition of wet acidic solutions or dry acidic particles from air. Detrimental consequences include abnormal bone development in fish, damage to limestone structures and monuments, damage to metal surfaces, and death of many kinds of trees and other vegetation.
Although carbon dioxide is a naturally occurring substance, much larger quantities are put into the atmosphere as a waste product of energy production. This increased amount allows light and heat to pass through the atmosphere to the earth’s surface but hinders its reradiation back into space.
If the ozone layer was destroyed, more ultraviolet light would reach the earth’s surface, causing increased skin cancers and cataracts in humans and increased mutations in all organisms.
Since most air pollution results from the burning of fossil fuels, energy conservation would decrease the amount of fossil fuels burned and reduce the amounts of carbon monoxide, HC, sulfur dioxide, and other pollutants in the atmosphere.
