The Hollies sang that all they needed was “the air that I breathe, and to love you.”

Yorkers in need of the same might hope their loves live in Wyoming.

York County was again listed on the American Lung Association’s list of 25 places with the worst air quality, according to the 12th annual State of the Air Report released Wednesday morning.

The York-Hanover-Gettysburg metropolitan area tied for 25th worst for year-round particle pollution, also known as sooty exhaust. York has made the list since the association first started compiling data in 2004.

Such pollution, according to the association, can interfere with the development of the growing lungs of children and increase the risk of heart disease, lung cancer and asthma attacks in children and adults.

The individual particles are so small they can only be seen through a microscope, but they form a haze when millions of them come together.

If there’s a silver lining, it might be that the numbers have actually improved since last year.

Getting better? The York area and all but two other areas on the list improved, a sign that the Clean Air Act is doing what it was intended to do, said Charles Connor, president and chief executive officer of the American Lung Association.

He and other staff at the association praised the law’s significance several times Tuesday during a press conference and vowed to fight corporate lobbyists who are pushing Republicans in the House of Representatives to support a bill that would lower cleanliness standards.

Kevin Stewart, Lancaster-based director of environmental health at the Lung Association, said York’s numbers improved because of increased standards for coal-burning power plants, diesel engines and diesel fuel.

York has one coal-burning plant, PPL Corp.’s Brunner Island Steam-Electric Station in East Manchester Township, which in 2009 underwent major changes to reduce its emissions.

Stewart said the economic recession also contributed to the improvement because companies had less work and were creating less pollution.

While the York area creates its share of pollution, it’s also the unfortunate recipient of pollution from some neighbors, he said.

York is downwind from two major air pollution sources, he said, the coal-burning power plants of Western Pennsylvania, and the Ohio Valley and the Baltimore-Washington-Northern Virginia metro area.

“But a substantial part is our doing,” he said.

Underachiever: The report also grades cities and counties for their number of high ozone days, and York County was given an F for having logged 27 “high-ozone” days during the three-year study period.

The county was graded a slightly better “D” for its number of high particle pollution days between from 2007-2009, despite being in the 25 worst.

Dr. Norman Edelman, the association’s chief medical officer, said the health effects from the pollutants include everything from wheezing, coughing and pediatric asthma attacks to chronic bronchitis and cardiac disease.

At particular risk are children and teens – who are more likely to play outside and whose lungs are still developing – and adults age 65 and older or those living with lung or heart disease or diabetes.

Across the nation, the cleanest city for year-round particle pollution was Cheyenne, Wyo.

-Reach Christina Kauffman at 505-5436, ckauffman@yorkdispatch.com, or follow her on Twitter at @dispatchbizwiz.