The U.S. Environmental Protection Agency (EPA) released its annual report on air quality, tracking our nation’s progress in improving air quality since the passage of the Clean Air Act. “Our Nation’s Air: Status and Trends Through 2018” documents the considerable improvements in air quality across America since 1970.
The report released today shows that between 1970 and 2018, the combined emissions of six key pollutants dropped by 74 percent, while the U.S. economy grew 275 percent.
From 2016 to 2018, emissions of key air pollutants continued to decline:
- Nitrogen Oxides (NOx) ↓ 8.7 percent
- Particulate Matter 2.5 (PM 2.5) ↓ 1.9 percent
- Particulate Matter 10 (Including lead) (PM 10) ↓ 1.2 percent
- Sulfur Dioxide (SO2) ↓ 7.8 percent
- Carbon monoxide (CO) ↓ 7.2 percent
- Volatile Organic Compounds (VOC) ↓ 3.3 percent
In addition, average concentrations of harmful air pollutants decreased considerably across our nation between 1990 and 2018:
- Ground-level ozone (8-hour) ↓ 21 percent
- Fine Particulate Matter (annual) ↓ 39 percent (from 2000)
- Coarse Particulate Matter (24-hour) ↓ 26 percent
- Sulfur dioxide (1-hour) ↓ 89 percent
- Nitrogen dioxide (annual) ↓ 57 percent
- Lead (3-month average) ↓82 percent (from 2010); and
- Carbon monoxide (8-hour) ↓ 74 percent
EPA examines long-term trends to track the nation’s progress in cleaning the air. Air quality concentrations can vary year to year, even as human-caused emissions continue to decline. Variations in weather and natural events such as dust storms and wildfires can have an impact on air quality in affected areas. As a whole, human-caused emissions of the six common pollutants dropped in 2018, continuing the long-term trend. Despite this, the report shows that monitors in some areas logged increases in concentrations of particulate matter in the outdoor air, due in part to natural events such as wildfires. The increases in these areas had a small, but noticeable, impact on the national average.
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.