The Smog Blog: Cleaner Air Translates Into Longer Life
Posted by
Deborah Shprentz
|
January 21, 2009
A stunning new study published in the New England Journal of Medicine finds that average life expectancy in U.S. cities has increased nearly three years over recent decades, and approximately five months of that increase, or 15 percent, came because of reduced fine particle air pollution.
The study by researchers at Brigham Young University and the Harvard School of Public Health examined changes in air pollution in 51 cities across the nation between 1980 and 2000 and residents’ life expectancies during that period. The scientists applied advanced statistical techniques to account for other factors that could affect average life spans, such as smoking, income, and education.
For every decrease of 10 micrograms per cubic meter of particulate pollution in a city, the residents’ average life expectance increased by more than seven months.
The study found improvements in life expectancy even in cities that initially had relatively cleaner air, suggesting that further improvements in air quality will yield important public health benefits.
“There is an important positive message here that the efforts to reduce particulate air pollution concentrations in the United States over the past 20 years have led to substantial and measurable improvements in life expectancy,” said study co-author Douglas Dockery, of the Harvard School of Public Health.
In an editorial commenting on the study, Dr. Daniel Krewski of the University of Ottawa wrote: “the strength of the study by Pope et al. resides in its ability to demonstrate an increase in life expectancy resulting from actual reductions in particulate air pollution. This finding provides direct confirmation of the population health benefits of mitigating air pollution and greatly strengthens the foundation of the argument for air quality management.”
The study is available online at www.nejm.org.
