BALTIMORE (WJZ)– A new study by the American Lung Association (ALA) is showing mixed results for the air we’re breathing in the Baltimore-Washington area.

Alex DeMetrick reports it’s because there’s more than one way to pollute the air.

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First the good news.

According to the ALA, it’s not as smoggy here as it used to be.

“We’re very pleased to report it’s improved significantly in this report,” Janice Nolen of the ALA said.

In 1990, the Baltimore-Washington area was ranked the third worst smog zone in the country. Only Los Angeles and New York were worse.

Currently, the ALA study says our area is 13th for smog days, out of 277 metro areas across the country. Why?

“A lot of it comes from coal-fired power plants being cleaned up,” Nolen said.

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One plant in South Baltimore is an example. Millions were spent to send more steam than pollution into the air.

While smog levels have improved, other types of air pollution remain high, including articulate pollution– microscopic bits sent into the air by exhaust from trucks and cars.

Where traffic is heaviest, the greater the exposure to those particulates.

“You see the trucks right now, riding up and down the streets all day,” Charles Glover, a resident of Brooklyn, said.

In the Brooklyn-Curtis Bay area, it’s very high.

“They do go deep into the lungs and some are so small, they can actually pass into the bloodstream,” Nolen said.

“The Code Orange, the Code Red days. People complaining of sinus headache, congestion. Their nose and eyes are burning, and the asthmatics have had to increase their medicines,” Dr. John Bacon, an allergy/immunology specialist, said.

Because even with improvements, there are still days it’s hard to breathe.

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According to the ALA, 127 million Americans– or 40 percent of the population– live in areas with high levels of air pollution.