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Air and Health

National air quality has improved since the early 1990's, but many challenges remain in protecting public health and the environment from air quality problems.

Since the 1950s, air quality has been a major public health and environmental concern. Local, state, and national programs have helped us learn more about the problems and how to solve them.

CDC works closely with the U.S. Environmental Protection Agency to provide air quality data on the tracking network and to better understand how air pollution affects our health. The Tracking Network includes information about the possible health effects of exposure to ozone, particulate matter (PM2.5), benzene, and formaldehyde.

Ground level ozone

Elderly man sitting on bench coughing in tissue Your exposure to ozone depends mainly on where you live and work and how much time you spend outside. Everyone can have health problems from ozone. Symptoms might be very mild or more serious. People with lung disease, children, older adults, and people who are active outdoors are at the highest risk of having problems when ozone levels are unhealthy.

Many scientific studies have linked ground-level ozone contact to varied problems, such as

  • lung and throat irritation,
  • wheezing and breathing difficulties during exercise or outdoor activities,
  • coughing and pain when taking a deep breath,
  • aggravation of asthma, bronchitis, and emphysema, and
  • higher chance of getting respiratory illness like pneumonia or bronchitis.

Particulate Matter

Particle pollution, or particulate matter, consists of particles that are in the air, including dust, dirt, soot and smoke, and little drops of liquid. Some particles, such as soot or smoke, are large or dark enough to be seen. Other particles are so small that you cannot see them. Small particles are the most concerning because they are most likely to cause health problems. Their small size allows these particles to get into the deep part of your lungs. Being exposed to any kind of particulate matter may cause

Middle-aged woman using asthma inhaler

  • increased emergency department visits and hospital stays for breathing and heart problems,
  • breathing problems,
  • asthma symptoms to get worse,
  • adverse birth outcomes, such as low birth weight,
  • decreased lung growth in children,
  • lung cancer, and
  • early deaths.

Sensitive people, including older adults, people with diseases such as asthma or congestive heart disease, and children, are more likely to be affected by contact with PM2.5.


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