What You Can't See Can Kill You

One day last July, a power plant smokestack rained black soot on the farms and homes of Shippingport, Pa., CBS News correspondent Wyatt Andrews reports.

The power company, First Energy, said it was a maintenance accident — and, according to local residents, warned them not to eat anything dusted by the soot.

The accident, which had the power company power-washing a town, was an unusually severe and visible example of what Americans breathe — in much smaller amounts — every day. And not just from power plants: Trucks, cars and even fires produce microscopic soot particles and chemicals that can damage your lungs.

"Particle pollution, soot, kills people," says Janice Nolan with the American Lung Association

The American Lung Association is one of many leading medical groups demanding that the Bush administration adopt stricter controls on microscopic soot. These groups cite overwhelming evidence linking microscopic particles to fatal diseases.

Tens of thousands of people die "every year, from soot-based heart attacks, cancer, strokes," Nolan says.

Despite that evidence, when the Environmental Protection Agency had the chance to set a tough new annual emissions standard for soot this year, the agency declined. The EPA also declined a request by CBS News to explain that decision on camera, but in a written statement said, "EPA's air-quality standards are the most health-protective in U.S. history. ..."

Dr. Roger McClellan, an EPA adviser, agrees with the agency; he says none of the research cited by critics proves that tougher standards will save lives.

"They are just stretching the scientific data. And I think that has been used excessively to try to scare the public into thinking these are real deaths," McClellan says.

However, in a 20-2 vote last year, an independent committee of scientists advising the EPA said tighter annual control on microscopic soot would save lives.

When EPA dismissed this, critics said the Bush administration was ignoring science to go easy on industry.

Meanwhile, the power company in Shippingport is now telling residents it's safe to eat vegetables if they're washed. But remember, the black rain that fell that day was pollution you could see. On every other day, it's what you can't see that could kill you.