If there was why is the air so polluted in Los Angeles?

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The air is polluted by the remaining heavy industry.

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The report found that 22 of the 25 most ozone-polluted cities improved their air quality in the past year.

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This is when the air was more polluted there.

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For pollution levels, we used information from the American Lung Association's "State of the Air: 2007" report, which ranked the most polluted metropolitan areas by year-round particle pollution based on data submitted by states to the U.S. Environmental Protection Agency for 2003-05.

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Up to 9% of deaths in the capital's most polluted areas are down to air pollution, a new London Assembly paper has reported.

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The organization's recent State of the Air 2012 report found that California is home to many of the country's most polluted cities, with Los Angeles continuing to top the list of ozone-polluted cities thanks to its heavy road traffic and trade ports.

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