An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

News Releases

News Releases from HeadquartersAir and Radiation (OAR)

EPA Celebrates 50 Years of Protecting Our Nation's Air

Criteria air pollutant emissions - and their precursors - dropped 7 percent under President Trump

Contact Information: 
EPA Press Office (

WASHINGTON (June 8, 2020) — Today, the U.S. Environmental Protection Agency (EPA) released its annual report on air quality, tracking the nation’s progress through 2019. “Our Nation’s Air – EPA Celebrates 50 Years!” documents remarkable improvements in air quality across America since 1970, and particularly over the last few years under President Trump.

“Under President Trump, Americans are breathing the cleanest air ever recorded,” said EPA Administrator Andrew Wheeler. “Under President Trump, air pollution has declined seven percent. The Trump administration has shown that improvements in both public health and economic growth can take place at the same time.”

From 2017 to 2019, the combined emission of criteria pollutants and their precursors dropped 7%.

In the past three years under President Trump, we saw the following drops in emissions of criteria and precursor pollutants: 

  • Nitrogen Oxides (NOx) ↓10 % 
  • Particulate Matter 2.5 (PM 2.5) ↓1 %
  • Sulfur Dioxide (SO2) ↓ 16%
  • Carbon monoxide (CO) ↓ 6%
  • Volatile Organic Compounds (VOC) ↓ 3%

Administrator Wheeler previewed the air trends report in Grand Rapids also noting that as a result of these falling emissions under President Trump, in 2019 we saw a significant improvement in air quality. From 2017 – 2019, the number of days listed as unhealthy for sensitive groups in the Air Quality Index dropped by 34 percent as the amount of criteria pollutants in our air continued to fall:

  • Carbon Monoxide 8-Hour ↓ 10%
  • Lead (Pb) 3-Month Average ↓ 28%
  • Nitrogen Dioxide Annual ↓ 4%
  • Nitrogen Dioxide 1-Hour ↓ 2%
  • Ozone 8-Hour ↓ 4%
  • Particulate Matter 10 microns 24-Hour ↓ 22%
  • Particulate Matter 2.5 microns Annual ↓ 7%
  • Particulate Matter 2.5 microns 24-Hour ↓ 12%
  • Sulfur Dioxide 1-Hour ↓ 10%

Between 1970 and 2019, the combined emissions of criteria and precursor pollutants dropped by 77%, while the U.S. economy grew 285%.

From 1990 to 2019, emissions of air pollutants continued to decline:

  • Nitrogen Oxides (NOx) ↓ 65% 
  • Particulate Matter 2.5 (PM 2.5) ↓ 36%
  • Particulate Matter 10, including lead (PM 10) ↓ 30%
  • Sulfur Dioxide (SO2) ↓ 91%
  • Carbon monoxide (CO) ↓ 69%
  • Volatile Organic Compounds (VOC) ↓ 47%

Driven largely by federal and state implementation of stationary and mobile source regulations, from 1990 to 2017 emissions of hazardous air pollutants dropped 74%.

These emission reductions have resulted in considerably improved air quality. Air quality monitoring data show that national average concentrations of harmful air pollutants decreased considerably across the nation between 1990 and 2019:

  • Ground-level ozone (8-hour) ↓ 25%
  • Fine Particulate Matter (annual) ↓ 43% (from 2000)
  • Coarse Particulate Matter (24-hour) ↓ 46% 
  • Sulfur dioxide (1-hour) ↓ 90%
  • Nitrogen dioxide (annual) ↓ 59%
  • Lead (3-month average) ↓85% (from 2010)
  • Carbon monoxide (8-hour) ↓ 78%

The report includes interactive graphics that enable citizens, policymakers and stakeholders to view and download detailed information by pollutant, geographic location and year. Explore the report and download graphics and data here:

The Air Trends report is one of many EPA resources tracking pollution trends and showing U.S. progress in improving the environment. Learn more at the following sites: