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Outdoor Air Pollution

Outdoor Air Pollution

graphic of people wearing masks in foreground and factories in the background

Have you ever noticed smog over a big city?

Then you’ve actually seen outdoor air pollution.

Some outdoor air pollution is invisible to us, of course, but it can still affect our lives.

Where does outdoor air pollution come from?

Many factors play a role in outdoor air quality. Natural things like volcanic eruptions, wildfires, wind currents, and trees can affect it. Some human activities add pollutants into the air. Think of factories and power plants pumping out smoke and chemicals, and tractors on farms blowing up dust clouds.

How can outdoor air pollution affect my health?

When we breathe in pollutants, they can create health problems — or make existing health problems worse. For example, they may trigger symptoms of asthma, or cause other kinds of breathing problems. Some polluters can cause more problems for some people than for others. Air pollution can also cause heart disease and cancer.

Some content courtesy of the National Library of Medicine.

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For parents
Air pollution can be indoors or outdoors. Particles in the air harm our lungs and make it difficult to breathe. Air pollution can cause a range of diseases. Learn more about air pollution.
For kids
Did you know the Clean Air Act is a federal law that that sets limits on common air pollutants released by industry and cars and trucks? By reducing air pollution, the Clean Air Act has led to major improvements in human health and the environment in the United States.
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