WASHINGTON (CN) - Despite drastic cuts in air pollution, more than 40 percent of Americans still live in areas with unacceptable air quality, according to an Environmental Protection Agency report released on Wednesday.
Over the last three decades, the levels of core pollutants in the U.S. have been cut in half despite a 34 percent growth in population size, a 90 percent increase in miles driven, and a 30 percent boost in energy use.
But the improvements -- credited to nation-wide regulations on cars and other industries -- still leave 127 million Americans in areas that fall short of federal standards for levels of lead, sulfur dioxide, particle pollution and ground-level ozone, according to the EPA's report entitled "Our Nation's Air Status and Trends Through 2008."
The Obama Administration has pressed for better air quality with an executive order last year requiring an increase in fuel efficiency from the current 25 miles per gallon to 35.5 miles per gallon by 2016.
Pollutants from internal combustion engines and other sources contribute to diseases such as asthma, cardiovascular problems and permanent lung damage.
Sulfur dioxide emissions alone are estimated to kill more than 24,000 Americans a year.
National levels of lead fell by 92 percent over the last three decades. Air also saw an 80 percent cut in carbon monoxide levels, a 70 percent cut to sulfur dioxide levels, a 46 percent decline in nitrogen dioxide levels, and a 25 percent fall in ground-level ozone levels.
Particulate matter fell by nearly 20 percent over an eight-year period, said the EPA's Wednesday statement on air trends.
As a result of the cuts, nitrogen monoxide and carbon monoxide levels throughout the country now satisfy federal standards.
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