Philly-area air quality improves - but still among worst

The Philadelphia metropolitan area's air quality has improved over the last decade, but still remains among the worst in the country, concludes the American Lung Association's annual report on air pollution.

"State of the Air 2013" uses data collected by the federal Environmental Protection Agency to analyze three measures of pollution: smog, daily particle pollution, and year-round particle pollution. Based on the results, the report ranks metropolitan areas and counties from worst to best.

The Philadelphia region, defined as 13 counties in Pennsylvania, New Jersey, Delaware, and Maryland, saw improvements in annual particle pollution and slightly fewer days of serious smog, which is primarily made up of harmful ozone.

However, the Philadelphia region still ranked 22d worst for daily particulates, 10th worst for annual particulates, and 16th worst for smog.

"The air in the Philadelphia region is certainly cleaner than when we started the State of the Air report 14 years ago," said Deb Brown, president of the lung association of the Mid-Atlantic. "But the work is not done."

Six cities, previously ranked among the most polluted, improved enough to fall off the list, including Lancaster and York, Pa.

The lung association attributes the progress in cleaning air pollution to the federal Clear Air Act, passed 40 years ago. Recently, the association led the fight for tougher limits on particle pollution, announced in December by the EPA.

Despite progress, the new report found that 42 percent of people in the United States live with unhealthy levels of either ozone or particle pollution.