Air Quality Trends - Much Improved

EPA creates air quality trends using measurements from monitors located across the country. The table below shows that air quality based on concentrations of the common pollutants has improved nationally since 1980.

Percent Change in Air Quality
 1980 vs 20131990 vs 20132000 vs 2013
Carbon Monoxide (CO)-84-76-59
Ozone (O3)  (8-hr)-33-23-18
Lead (Pb)-92-87-60
Nitrogen Dioxide (NO2) (annual)-58-50-40
Nitrogen Dioxide (NO2) (1-hour)-60-46-29
PM10 (24-hr)----34-30
PM2.5 (annual)-------34
PM2.5 (24-hr)-------34
Sulfur Dioxide (SO2) (1-hour)-81-76-62
1. --- Trend data not available
2. Negative numbers indicate improvements in air quality
3. In 2010, EPA established new 1-hour average National Ambient Air Quality Standards for NO2 and SO2

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