The nation’s efforts to clear the air of pollution are paying off big time, according to new research published in the New England Journal of Medicine. Americans today live an extra five months, thanks to improvements in air quality achieved over the past few decades, the study found. In the cities that made the biggest improvement in air quality, life expectancies climbed a full ten months.

The good news comes from an analysis of 51 cities across the nation conducted by researchers at Harvard School of Public Health and Brigham Young University. The scientists compared two sets of data: changes in air pollution between about 1980 and 2000 and residents’ life expectancies during that same stretch.

On average, residents were living 2.72 years longer at the end of the two-decade period. Using statistical models, the scientists tried to account for all factors known to affect life span, including income, education, and cigarette smoking, among others. Their conclusion: cleaner air accounted for about 15 percent of the increased longevity, the equivalent of five months.

Previous studies have shown that air pollutants–including tiny particulates smaller than 4/100th the width of a human hair–pose a serious risk to hearts and lungs. The current analysis found that for every decrease of 10 micrograms per cubic meter of particulate pollution, average life expectancy climbed by more than seven months.

“Such a significant increase in life expectancy attributable to reducing air pollution is remarkable,” said BYU epidemiologist C. Arden Pope III, who led the study. “We find that we’re getting a substantial return on our investments in improving our air quality. Not only are we getting cleaner air that improves our environment, but it is improving our public health.”

With a new administration pushing for even stricter emissions controls, we can hope to see even more progress on both fronts.

For more on environmental issues, check out one of our favorite environmental blogs, Greeneroo.

© 2009 PDQhealth

Tags: air pollution, emissions, longevity, particulates