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Understanding What You Breathe

EPA scientists are monitoring and analyzing air pollution to develop ways to trace pollutants to their source, and help air quality managers prioritize action.

Air pollution monitors

Breathing is our one common constant. No matter what else you’re doing, who you are, or where you happen to be at any given moment, you are always in some stage of breathing.

The average adult breathes in more than 3,000 gallons of air every day. While the quantity of air we all breathe may be roughly the same, the quality is not.

Millions of people live in areas, particularly cities, where air pollution—smog, particulate matter, ozone, and a mixture of pollutants—makes the very act of breathing a health concern.

The air we breathe can be polluted by a variety of sources, from power plants and other industry located hundreds of miles away, to sources closer to home such as motor vehicles on nearby roads, local industrial plants, and even lawnmowers in our own backyard. Knowing the sources of air pollution is important to health officials and air quality managers, who are always looking for effective ways to clean the air.  For them, every breath is local. 

EPA scientists are working to develop tools and models that can track air pollution to its source.  

One such effort is the Cleveland Multiple Air Pollutant Study (CMAPS), a collaborative effort to investigate air pollution and the distribution of pollutants across Cleveland and the surrounding metropolitan area.

Cleveland was chosen as a study location because the city’s air quality is affected by numerous local and regional air pollution sources. Additionally, existing air monitoring sites in Cleveland have shown pollution levels exceeding current national ambient air quality standards for particulate matter.

Through a combination of annual and intensive month-long studies, scientists are collecting data on a host of pollutants: particulate matter, mercury, ozone, carbon monoxide, sulfur dioxide, nitrogen dioxide, black carbon (soot), and ammonia. Continuous measurements will provide researchers with detailed information on pollutant concentrations over time.

The scientists will analyze the air samples in search of chemical components that can be used, like a chemical fingerprint, to trace air pollutants back to their source.

"The combination of measurements taken provides new information on local, urban, and rural differences for a wide range of air pollutants," explains EPA's Dr. Gary Norris, one of the study’s principal investigators.

The science can lead to more targeted, cost-effective clean air actions focused on local populations. For example, if analysis shows that motor vehicles are the main source of air pollution in a given area, then actions that reduce driving and call for new fuel mixtures would be effective. On the other hand, if scientists find that a particular industry is a primary source of air pollution for an area, then pollution-control equipment would be the best investment for cleaner air.

Either way, local residents would be breathing easier.

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