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Outdoor Air PollutionOutdoor Air Pollution

The Basics

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 these pollutants, they can create health problems — or make existing health problems worse. For example, it may trigger symptoms of asthma, or cause other kinds of breathing problems. Air pollution can also cause heart disease and cancer.

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.

Learn More

Explore the links below to learn more about outdoor air pollution, including what experts are doing to deal with the problem — and how you can protect yourself.


Read About It Read About It

Air Pollution ( - Effects of air pollution on health and how to protect yourself.

Air Quality and Health (World Health Organization) - Key facts on air pollution as a major environmental health risk. Information on ozone, nitrogen dioxide, and sulfur dioxide.

Criteria Air Pollutants (U.S. Environmental Protection Agency)

Effects of Common Air Pollutants (PDF, 591.21 KB)(U.S. Environmental Protection Agency) - PDF on respiratory and cardiovascular effects of common air pollutants.

Healthy Air Outdoors (American Lung Association) - Resources on threatening outdoor air pollution, getting involved with clean air efforts, and defending the Clean Air Act.

Outdoor Air (Tox Town - National Library of Medicine) - Information on outdoor air pollution with links to Medline Plus, agencies with information, and chemicals found in the air.

Outdoor Air Pollution (National Library of Medicine) - Information about outdoor air pollution, and links to Medline Plus, agencies, and hazardous chemicals.

Ozone, Air Quality, and Asthma (KidsHealth from Nemours) - Information about air pollutants such as ground level ozone, and their health effects, including asthma.

Pollution: There's Something in the Air (Johns Hopkins University Ecohealth) - Describes air pollution, human health effects, and information on smog.

Risk Assessment for Toxic Air Pollutants: A Citizen's Guide (U.S. Environmental Protection Agency) - Information on toxic air pollutants, health risks, and risk assessments.

Games and Activities Games and Activities

Smog City 2 (U.S. Environmental Protection Agency) - Interactive air pollution simulator website; how individual choices, environmental factors, and different types of land use can affect air pollution.

Videos Videos

Monte Mold Chronicles (National Library of Medicine) - Join Monte Mold as he helps to explain how mold grows, its benefits to humans and the environment, and the potential risks to human health.

For Teachers For Teachers

ECybermission - Accept the Challenge (U.S. Army) - Education outreach program promoting the creation of eCYBERMISSION teams to research environmental issues.

The Air We Breathe (Teach Engineering) - Lesson plan to teach students how engineers work to reduce air pollution by understanding the causes of air pollution.

Trees and Air Quality (Wisconsin Department of Natural Resources) - Lesson plan for grades 4-9 to teach ways in which trees benefit air quality and how landscaping can decease energy use.

Understanding Air: Air Pollution and Modeling Pollutants with LEGO® Bricks (Public Broadcasting Services (including their teacher resources)) - Explore the connection between air quality and environmental health when students learn what happens when pollutants are exposed to sunlight.