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Clean Air Research


1. Can air pollution harm only lungs?

Decades of research have led scientists to understand the links between air pollution and serious health effects. Although early research focused on health effects to the lungs, recent research has revealed that the air we breathe may contain contaminants that are harmful to other organs such as the heart and brain or biological systems. Evidence from new research links air pollution to cardiovascular disease and even death.

EPA research continues to investigate the many health effects that can result from exposure to air pollution. Science produced the Clean Air Research Program provides the foundation for much of our knowledge about the health outcomes of air pollutants, particularly ozone, PM, and other common air pollutants.

2. Why study indoor air quality?

Americans spend 90 percent of their time indoors where pollutant levels can frequently exceed those found outdoors. This is because indoor air can include outdoor pollutants that seep inside as well as pollutants from indoor sources. These high levels of pollutants can cause a variety of health effects, including respiratory health problems and worsening of asthma.

EPA conducts research on indoor air quality to:

  • Understand indoor sources and the penetration of outdoor pollutants indoors
  • Determine exposures and health risks to common indoor pollutants
  • Develop prevention and mitigation strategies

3. Where is air pollution monitored?

Air quality monitoring networks are located across the United States to provide the critical information necessary to develop and implement air quality regulations and policies. EPA scientists conduct studies to develop methods to support monitoring networks. Instruments for sample collection or for standard monitoring are also developed or evaluated for widespread use.

These monitoring networks also provide data used on the AIRNow website that provides daily air quality forecasts and real-time air quality maps.

4. Why study air pollution sources?

Air pollution can come from a variety sources, both man-made and natural. Examples of air pollution sources include vehicle emissions, smokestacks, construction, agricultural practices and forest fires.

Research on air pollution sources sharpens air quality models, yields innovative control methods and helps policymakers make management decisions. Scientists in the Clean Air Research Program are dedicated to advancing the science to understand sources of air pollutants through the development of new technology and other tools.

5. Why is multipollutant research important?

Humans and ecosystems are exposed to a mixture of pollutants in the air.  It has become increasingly clear that multiple pollutants play a role in determining risks to people and the environment. EPA is moving forward with a "multipollutant" approach in air pollution research which will focus on:

  • Understanding the relationships between sources of air pollutants and atmospheric transformation (secondary) air pollutant products
  • Understanding the health risks posed by mixtures of air pollutants
  • Advancing atmospheric and exposure modeling of multipollutants
  • Developing methods and controls for sources or air pollutants that impact health relevant emissions or products
  • Determining a hierarchy of sources and related emission components regarding relative health risks

6. Does climate change impact air quality?

EPA is pursuing research to understanding how climate change and air quality interact and the consequences for public health and the environment. EPA scientists have already provided evidence that future temperature increases will increase air pollution levels in some regions of the country. What’s more, urban areas already suffering from pollution problems may incur the greatest burden of these changes.

An EPA report on the potential impacts of climate change on regional U.S. air quality is intended for managers and scientists working on air quality issues.  The report is entitled, "Assessment of the Impacts of Global Change on Regional U.S. Air Quality: A Synthesis of Climate Change Impacts on Ground-Level Ozone"

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