Data is released from the American Lung Association's "State of the Air" report Wednesday, and Delaware counties garnered grades ranging from A's to F's.
Director of Environmental Health for the American Lung Association Kevin Stewart said soot, burnt up carbon and chemical emissions are all particles found in the air.
"Some of those particles can even have, on the surfaces of them, air toxins and absorb certain chemicals that get picked up," Stewart said. "And so when you breathe these really microscopic particles, they can get into the deepest parts of the lungs and even cross into the bloodstream where they're particularly hazardous, certainly for people with lung disease, but especially for people with cardiovascular disease, and can even cause pre-mature death," says Stewart.
New Castle County -- which is lumped into the Philadelphia-Camden-Vineland metropolitan area -- is ranked 11th most polluted for ozone and year-round particle pollution.
But the state can't necessarily control the pollutants in the air.
"And so not all of these grades are the cause of pollution that's generated in Delaware," Stewart said. "But some of it, of course, comes from the Philadelphia area, some of it comes from Baltimore-Washington area, and even some places farther West, out in the Ohio Valley and Mississippi River even," he said.
Kent and Sussex counties were among the cleanest for daily particle pollution and scored A's.
"The Dover metro-area, in Kent County, getting a grade of A for its short-term particle pollution -- or soot pollution -- level, which means it had zero bad air days for that pollutant during the years of 2009 to 2011," Stewart said.
All of the air scores are available on the State of the Air website.
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