Most fine particulate pollution is formed in the atmosphere by a combination of emissions, especially the carbon, sulfur dioxides and nitrogen oxides produced by machines that burn fossil fuels.

U.S. Environmental Protection Agency research shows that PM2.5 — microscopic particles that are drawn deep into the lungs, and sometimes the bloodstream — can aggravate lung and cardiovascular diseases and have been associated with a variety of serious health problems including heart attacks, chronic bronchitis and asthma attacks.

Carol Kemker, an EPA spokeswoman, said Friday that requiring states to reduce fine particle pollution is just one element of the Bush administration’s national strategy for clean air.

A recent EPA rule puts restrictions on emissions from nonroad diesel engines, she said, and the proposed Clear Skies legislation and Clean Air Interstate Rule focus on the bigger picture.

“This administration is committed to addressing emissions that move across state lines,” she said, “particularly with regards to power plants.”

With Plant Hammond in Floyd County and Plant Bowen in Bartow County, Northwest Georgia is home to two of the country’s major producers of sulfur dioxides.

Georgia Power spokesman John Sell said the company plans to spend at least $1.3 billion during the next five years to add pollution controls to its Georgia plants.

“The electric companies are one of the more regulated industries, and a number of new federal rules are going to cause us to put more air-quality controls on our plants,” he said.

The company already has filed permits with the EPA and called for proposals to install two scrubbers at Plant Bowen. Sell said the scrubbers, which cut sulfur dioxide emissions, should be in service by 2008.

“You can’t just go to the store and buy them,” he said. “There’s a lot of retrofitting involved.”

Sell said there is some concern in the industry that the new national regulations will tax pollution-control resources. The number of suppliers and qualified installers is limited, he said.

He also said restricting power plants is not the sole solution to PM2.5 pollution.

“Sulfates come from power plants, but carbon comes from transportation like cars and trucks,” he said. “And the negative health effects, according to studies I’ve seen, come from the carbon.