Americans Are Living Longer, Thanks to the Clean Air Act

Americans have gained 336 million life-years since the Clean Air Act was passed in 1970, according to researchers at the University of Chicago

Join Our Community of Science Lovers!

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


When the Clean Air Act was passed in 1970, Los Angeles was known as the “smog capital of the world” and Steubenville, Ohio was about as polluted as Beijing, according to University of Chicago’s Michael Greenstone.  But, Greenstone says, the air is a lot cleaner today. In turn, increases to life expectancies have been realised across the nation.

This is not to say that the Clean Air Act’s work is done. In truth, air pollution is still a significant challenge in the United States. For example, air pollution from combustion processes – primarily from transportation and power generation – results in an estimated 200,000 early deaths across the country each year. But, the nation's air is certainly getting cleaner.

This trend can be seen by looking at particulate matter concentration data from 1970 to 2012 from the U.S. Environmental Protection Agency (EPA), Greenstone's team was able to calculate changes in life expectancy for metropolitan areas across the nation. For example, according to their results, the following life expectancy increases were seen in these metro areas:


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


  1. Weirton, West Virginia (+5.2 years)

  2. Wichita, Kansas (+4.3 years)

  3. Phoenix, Arizona (+3.9 years)

  4. New Castle, Pennsylvania (+3.9 years)

  5. Mobile, Alabama (+3.9 years)

  6. Youngstown, Ohio (+3.4 years)

  7. Chattanooga, Tennessee (+3.0 years)

  8. Pueblo, Colorado (+2.9 years)

  9. Kingsport, Tennessee (+2.9 years)

  10. Birmingham, Alabama (+2.8 years)

  11. Los Angeles, California (+1.7 years)

  12. Houston, Texas (+0.9 years)

 

Subscribe to Support Independent Journalism

Great science journalism requires human expertise, time, effort and creativity. And it costs money. That’s why I and the journalists here at Scientific American hope you’ll join our community.

When you subscribe, you are supporting staff and freelance journalists who are passionate about telling science stories that are true, important and compelling. Our editors and reporters are often experts in their fields, which means they understand the nuances of big discoveries and can untangle the breakthroughs from the hype. With a subscription, you are also supporting rigorous fact-checking to ensure the words we publish are precise and accurate. And you’re supporting original illustrations, graphics and photos that bring you closer to an advanced laboratory, an ice sheet in Antarctica or a space mission in orbit. You’re helping us craft other types of high-quality journalism as well: Our newsletters are carefully written, edited and curated by staffers you have or will come to know and love. Our Science Quickly podcast is based on original reporting, collaboration with editors and scientists and exacting production.

Subscriptions keep this engine running so we can continue to deliver thoughtful, rigorous and independent science journalism to you. In an era of viral misinformation, this work is crucial. If you value what we do, I hope you’ll consider joining us as a subscriber

Thank you,

Jeanna Bryner, Editor in Chief, Scientific American

Subscribe