Pollution of the atmosphere from dumps, dust, odors, pesticides, vehicle exhausts, radiation, smoke, industrial gases, incineration smoke, and ash.
Harmful substances in the atmosphere. Air pollution causes damage to the environment and to human health and quality of life. Air pollution makes people sick by causing breathing problems, and it harms animals, plants, and the ecosystems in which they live. Air pollution has altered the atmosphere by letting in increased amounts of radiation from the sun, thereby increasing people’s risk of developing skin cancer. At the same time, air pollution traps heat in the atmosphere, which leads to global warming. Scientists warn that global warming caused by air pollution will eventually affect the world’s food supply, the sea level, weather, and the spread of tropical disease.
Air pollution is a major international medical problem and is being studied by governmental health departments throughout the world. Some evidence suggests that cancer is caused by the chemicals released into the atmosphere by automobile exhaust, chemical factories, and the burning of coal. The chief poisons causing concern are carbon particles, or soot, benzpyrene chemicals, lead, and sulfur dioxide. The carbon particles are released principally by gasoline and diesel engines. The benzpyrene chemicals are found in tobacco smoke and have long been associated with cancer. Lead emerges from the combustion of leaded fuels in motor cars and is a notorious poison. Sulfur dioxide reaches the atmosphere mostly from coal fires, dissolves in the air moisture, and forms the sulfuric acid responsible for the erosion of the stone surfaces of city buildings. Governments throughout the world have tried various methods to deal with these pollution problems. Western nations all agree that automobile emissions must be controlled, and several nations, including the United States, have set strict emission standards which went into effect in 1975. Many nations have also limited cigarette advertising in an attempt to cut down tobacco consumption. In the United States, cigarettes may not be advertised on television. Although many countries have depended almost exclusively on coal fires to produce their electricity, new smoke filtration methods have considerably reduced pollutants. Several countries are also investigating the possibility of nuclear power plants to produce electricity. When properly engineered and regulated, nuclear power plants produce no pollution at all.