Scientists reported on Wednesday in the New England Journal of Medicine that important improvements of the air quality in the United States have added 21 weeks to the lives of the American over the last 20 years. Thus, by reducing the smoke polluted particles given off by the cars, the diesel engines and the coal-fired power plants, there have been added 15% of the 2.72 years of extra longevity seen in the U.S. since 1980.

Arden Pope, an epidemiologist at Brigham Young University in Utah who led the study, stated that the most important reason for which the Americans have improved their life expectations is the change in smoking habits. Then, the improved socioeconomic conditions, estimated by the high school graduates living in the area, were also an important factor.

Yet, the cleaner air was a big and important issue. As Pope told Reuters, it was very shocking to see how the air pollution effects count this much on our lives. Together with his colleagues, Pope tracked the life expectancy, the economic and demographic data and the pollution data from 51 metropolitan areas.
They then found that the air pollution had dropped by 10 micrograms per cubic meter and the life expectancy grew by 31 weeks. Akron, Ohio and Philadelphia were the main areas were the results were very visible.

Pope added that these findings show that there has been a truly bonus given to the efforts made beginning 1970 as to improve the quality of the air. Daniel Krewski of the University of Ottawa, stated that the study shows very clear how does the air pollution affect the human health and drops the life expectancy.