Many Americans believe the air they breathe is getting cleaner. But in recent years, scientists have pieced together evidence showing that a largely unregulated class of pollutants--tiny dust particles known as fine particulates--may be causing thousands of deaths each year. These microscopic specks appear to lodge deep in the lungs, where they may cause long-term damage. "This research burst on the scene like a bombshell," says James N. Pitts Jr., a chemist and chairman of California's Scientific Review Panel for Toxic Air Contaminants.
Now comes the policy bombshell. On Nov. 29, the Environmental Protection Agency will propose the first health-based standard to control these fine particulates. Under pressure from an American Lung Assn. lawsuit, the agency is expected to set a standard regulating dust 2.5 microns in diameter or smaller. These particles have not previously been regulated. The regulations aren't expected to take effect until at least 2004.
"SOUND SCIENCE." But the coming proposal is already causing a brawl among environmental groups and industry powerhouses. Environmentalists say it is too little, too late. The Natural Resources Defense Council says the small particles are causing tens of thousands of premature deaths annually. Industry groups say the science is still too uncertain to be the basis for regulations that they claim would cost billions annually. In the middle of the fight is EPA Administrator Carol M. Browner, who states: "Our decision will be based on sound science. And the implementation will be cost-effective and common-sense."
That may not be so easy. Under the agency's proposal, now under review at the White House, the EPA will require cities to reduce the concentrations of particles 2.5 microns or smaller. (The EPA already regulates larger particles.) The maximum limit will be an average of 20 micrograms per cubic meter. The agency will also tackle another kind of air pollution--ozone. The maximum allowable concentration of ozone will drop from 0.12 parts per million over a one-hour period to between 0.07 to 0.09 parts per million over eight hours. The upshot: Under the new proposal, as many as 250 communities might find themselves in violation of standards for ozone and fine-particulate pollution.
New scientific evidence suggests action may be warranted. A landmark 1995 Harvard study found that tiny dust particles--linked to diesel exhaust, power plants, steel mills, and other sources--cause 100,000 deaths each year. The researchers found that people who live in cities most polluted by particulates face a 15% to 17% higher mortality rate than those living in the least polluted areas. "This is the most serious health threat we've seen since smoking," says Deborah Sheiman Shprentz, a research analyst at the Natural Resources Defense Council.
HIGH COST. The EPA's Clean Air Scientific Advisory Committee did not agree on what levels of fine particulates were safe because many felt the research was inadequate. "There's not much data out there yet," says George T. Wolff, committee chairman and a chemist with General Motors Corp.
Industry groups are seizing on the scientific uncertainty to squelch talk of new rules. The Air Quality Standards Coalition, spearheaded by the National Association of Manufacturers, plans to spend $1.5 million over the next six months probing the science of fine particulates. Their strategy is to call for more research instead of regulations. They fear regulations would have a devastating impact. "Every industry will be hit," says Boyden Gray, a lobbyist for Geneva Steel who was President Bush's White House counsel. "We just don't know who will be hit hardest."
For their part, activists want even stricter standards. The lung association has spent $50,000 on radio spots in Washington arguing that particulates are one of the nation's biggest pollution problems. "We'll keep the pressure on," vows lung association lobbyist Paul Billings. As the scientific evidence continues to mount, the nation may have to impose tighter regulations before the dust on this controversy finally settles.