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Ozone Angst

EPA proposes to tighten standard but will consider arguments for the existing one

by Cheryl Hogue
June 25, 2007 | A version of this story appeared in Volume 85, Issue 26

EPA'S PROPOSAL last week to ratchet down the allowable level of ozone pollution could leave the door open for the agency to bow to industry pressure for maintaining the status quo.

The agency on June 21 proposed to tighten the clean air standard for ozone, the main component of smog, from the current level of 0.08 parts per million to somewhere between 0.070 and 0.075 ppm. The existing standard, established in 1997, is set to two decimal places. The new one will be specified to three decimal places due to improvements in ozone measurement technology.

EPA Administrator Stephen L. Johnson says that, on the basis of scientific evidence, "I have determined that the current standard is insufficient to protect public health." Under the Clean Air Act, the EPA administrator can consider only health issues—and may not take into account costs—when setting allowable limits on air pollution.

Nonetheless, the agency said it will accept comments from the public for maintaining the current standard or favoring a new ozone limit as low as 0.060 ppm. This move could leave EPA wiggle room to keep the 0.08 ppm standard when the agency finalizes its decision in March 2008.

"EPA's smog proposal sends a mixed message," says Frank O'Donnell, president of the environmental group Clean Air Watch.

EPA and the White House are under pressure from industry to retain the 0.08 ppm limit. Business groups, including the National Association of Manufacturers, say a more stringent ozone standard will trigger expensive pollution control requirements and hurt the economy.

Meanwhile, the American Lung Association along with environmental and public health groups are calling for a tougher standard that would be more protective of public health than the one EPA proposed.

Johnson says there are no scientific justifications for retaining the current standard. But he defends EPA's plan to call for the public to offer arguments favoring the existing standard or a tighter one than EPA proposed.

"We will consider all comments as part of the deliberations" to finalize the ozone standard, Johnson says.



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