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air pollution

(Encyclopedia)air pollution, contamination of the air by noxious gases and minute particles of solid and liquid matter (particulates) in concentrations that endanger health. The major sources of air pollution are t...

pollution

(Encyclopedia)pollution, contamination of the environment as a result of human activities. The term pollution refers primarily to the fouling of air, water, and land by wastes (see air pollution; water pollution; s...

pollution allowance

(Encyclopedia)pollution allowance or emission rights, government-issued permit to emit a certain amount of a pollutant. The holder of the permit may use it to pollute legally, may trade permits, or may sell the per...

marine pollution

(Encyclopedia)marine pollution: see water pollution. ...

thermal pollution

(Encyclopedia)thermal pollution: see water pollution. ...

noise pollution

(Encyclopedia)noise pollution, human-created noise harmful to health or welfare. Transportation vehicles are the worst offenders, with aircraft, railroad stock, trucks, buses, automobiles, and motorcycles all produ...

water pollution

(Encyclopedia)water pollution, contamination of water resources by harmful wastes; see also sewerage, water supply, pollution, and environmentalism. The United States has enacted extensive federal legislation to ...

air

(Encyclopedia)air: see atmosphere; liquid air; ventilation. ...

liquid air

(Encyclopedia)liquid air, ordinary air that has been liquefied by compression and cooling to extremely low temperatures (see liquefaction). Its commercial preparation involves purification by washing to remove solu...

lock, air

(Encyclopedia)lock, air: see air lock.