May 1, 2007, 20:30 GMT
Los Angeles - Residents of Los Angeles can breathe a sigh of relief - or perhaps not. Their city was bestowed with the dubious honour Tuesday of having the most polluted air in the US according to the American Lung Association's annual state of the air report released Tuesday.
The Pittsburgh, Pennsylvania area ranked as the nation's second most polluted metropolitan area followed by Bakersfield, California; Birmingham, Alabama; Detroit and Cleveland, Ohio. Though Los Angeles' famous smog still persists, the city registered fewer days with bad ozone levels in 2006 than in previous years.
'Nobody is surprised that LA has an air pollution problem,' said Janice Nolen, the association's assistant vice president for national policy and advocacy. 'But it is important for folks to know that there has been some improvement.'
The lung association checked for three kinds of pollution: ozone and two kinds of soot - short-term and year-round exposure. It found that 136 million people lived in US counties with unhealthy levels of at least one of the three. Los Angeles was ranked as the most polluted city for all three categories.
But while smog levels are falling from their peak in 2002, the report noted that soot levels are rising in the densely populated eastern part of the country because of the use of coal-fired power plants.
The report follows an Environmental Protection Agency announcement Monday that preliminary data from 2006 shows that levels of six pollutants, including ozone and particulate matter, have declined 54 per cent since 1970, when the Clean Air Act became law.
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