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Country Spotlight: United States

Pollution Ranking

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Particulate Pollution (µg/m3) xx

Gain in life expectancy if WHO Guideline is met xx

*The WHO Standard is µg/m³.

Gain in life expectancy if National Standard is met xx

*There is no National Standard.

Studying pollution in the United States tells largely a success story. Part of the United States once had levels of pollution similar to Beijing in recent years. Los Angeles had become known as the smog capital of the world. And, other large metropolitan areas weren’t far behind. Pollution had become a part of everyday life for many Americans, and citizens made clear that they wouldn’t tolerate it any longer. The Clean Air Act was enacted in 1970, and since that time particulate pollution has declined by 66 percent—extending the life expectancy of the average American by 1.6 years. Forty-four percent of those reductions have occurred over the last twenty years.


  • For those living in the former smog capital of Los Angeles, particulate pollution has declined by almost 60 percent since 1970, extending life expectancy for the average Angeleno by 1.4 years. In Philadelphia and Washington, DC, a reduction in pollution has extended life expectancy by 2.7 years.
  • Only 11 percent of the population still lives in an area where particulate pollution exceeds the World Health Organization (WHO) guideline.
  • Residents of California’s Central Valley have consistently been exposed to particulate pollution above both the WHO guideline and the nation’s own air quality standard. Those living in this region stand to gain up to 0.4 years (8 months) of life expectancy if air quality were kept below the WHO guideline rather than at the 2018 level—a year when California saw intense wildfires that may have contributed to the pollution.
  • In the industry-heavy areas around Pittsburgh, Pennsylvania and in eastern Ohio, residents stand to gain 2 months if pollution were to improve.

Explore The Data

Data for Potential Change in Life Expectancy

10 States with Largest Potential Life Expectancy Gain
10 Most Polluted States

United States: Clean Air Act (1970)

With 66% less pollution, Americans are living healthier, longer lives.

Reductions in particulate air pollution alone, thanks in large part to the Clean Air Act, have added 1.6 years to the life expectancy of the average American since 1970.

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The Index

The AQLI converts air pollution concentrations into their impact on life expectancy. From this, the public and policymakers alike can determine the benefits of air pollution policies in perhaps the most important measure that exists: longer lives.

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The AQLI estimates the relationship between air pollution and life expectancy, allowing users to view the gain in life expectancy they could experience if their community met World Health Organization (WHO) guidelines, national standards or some other standard.

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