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Air Trends
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Sulfur Dioxide Trends

Air quality monitors measure concentrations of SO2 throughout the country. EPA, state, tribal and local agencies use that data to ensure that SO2 in the air is at levels that protect public health and the environment. Nationally, average SO2 concentrations have decreased substantially over the years. The charts below show national and regional trends in SO2 concentrations. For information on SO2 standards, sources, health effects, and programs to reduce SO2, please see our Sulfur Dioxide Pollution page.

National Trends

Starting in  1980 | 1990 | 2000 | 2010

 

Regional Trends

Region: Ohio Valley | Upper Midwest | Northeast | South | Southeast | Southwest | West | Northern Rockies and Plains

 
How to interpret the graphs
View US Climate Regions map
  • Air Trends Home
  • Air Quality - National Summary
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  • Particulate Matter (PM10) Trends
  • Particulate Matter (PM2.5) Trends
  • Sulfur Dioxide Trends
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on August 1, 2022
United States Environmental Protection Agency

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