Emissions from diesel engines will continue to kill thousands of Americans each year because newly introduced rules to limit diesel pollution will take years to take full effect, according to a report yesterday by an environmental organization.
Federal rules issued last year to control diesel pollution will ultimately usher in much cleaner diesel technology, said the report by the Clean Air Task Force, but because the rules do not apply to existing engines, the group called for an aggressive program to retrofit them with special filters.
"Diesel pollution cuts short the lives of 21,000 Americans a year," said Conrad Schneider, advocacy director at the Clean Air Task Force, who said the analysis used a methodology employed by the federal Environmental Protection Agency.
Industry groups said that the report inflates the risk and that voluntary programs to install filters are already underway.
The report has not been subjected to the kind of independent scrutiny that studies undergo before they are published in major scientific journals, but Dan Greenbaum, president of the Health Effects Institute, said the report used "state-of-the-art techniques." The institute is an independent, nonprofit research institute jointly funded by the EPA and industry to be an honest broker on the science of air pollution.
But Greenbaum said he is uncomfortable with the assertion that diesel emissions claim 21,000 deaths per year: "It's a mistake to pick a single number and say this is the truth. You have to look at all the things that put it in some perspective. It could be worse, but it could be lower, too."
Schneider's group said 21,000 deaths was the median number produced by their statistical model: The range was between 8,000 and 34,000.
Since diesel engines typically last as long as 30 years, it could be decades before Americans see the full health benefits of pollution-control rules issued by the Bush and Clinton administrations, Schneider said. In the meantime, there are 13 million diesel engines in the United States, including school buses and garbage trucks, spewing pollutants into the air.
The report called for increased government funding to clean up municipal vehicles and regulations to force private companies to install filters, which can cost as much as $5,000 a vehicle.
"Reducing diesel fine particle emissions 50 percent by 2010, 75 percent by 2015 and 85 percent by 2020 would save nearly 100,000 lives between now and 2030" over and above the health impact of the existing rules, the report said.
"I don't find it particularly helpful to scare people about the risks," countered Allen Schaeffer, executive director of the Diesel Technology Forum, which represents vehicle and engine manufacturers as well as companies that make emission-control devices. Schaeffer and Joe Suchecki, a spokesman for the Engine Manufacturers Association, said it would be a mistake to mandate filters on all engines and called for expanding voluntary programs and incentives.
Besides issuing rules for new diesel engines and encouraging voluntary retrofit programs, the EPA is also mandating cleaner diesel fuels, said spokeswoman Cynthia Bergman.
George Thurston, an associate professor in the department of environmental medicine at the New York University School of Medicine, said the report used the best available techniques, but he added that there are disagreements about many assumptions in such models.
Industry groups tend to overestimate the costs of cleanups, he said. And figuring out how much to spend to fight pollution is even more contentious because it involves judgments about how much each saved life is worth.
