April 22, 2008

Clear Link Found Between Smog and Premature Deaths

A new report by the National Academy of Sciences found that short-term exposure to smog, or ozone, has a clear link to premature deaths. The report, released Tuesday, said the link should be taken into account when determining the health benefits of reducing air pollution.

The findings run contrary to arguments made by some White House officials that the link between smog exposure and premature death has not been sufficiently proven, and that the link should not be considered in calculating the benefits of clean air.

But the new report, compiled by a panel of the Academy's National Research Council, advised government agencies to "give little or no weight" to such arguments.

"The committee has concluded from its review of health-based evidence that short-term exposure to ambient ozone is likely to contribute to premature deaths," the 13-member panel wrote, adding that "studies have yielded strong evidence that short-term exposure to ozone can exacerbate lung conditions, causing illness and hospitalization and can potentially lead to death."

The White House Office of Management and Budget (OMB), which raised questions about the link in its review of air quality regulations, did not immediately return calls from the Associated Press seeking comment.

"The report is a rebuke of the Bush administration which has consistently tried to downplay the connection between smog and premature death," Frank O'Donnell, president of Clean Air Watch, a Washington-based advocacy organization, told the AP.

Vickie Patton, the Environmental Defense Fund's deputy general counsel, said the Academy's report "refutes the White House skepticism and denial" of a proven link between acute ozone exposure and premature deaths. She said such arguments have been used to diminish the health benefits of reducing air pollution.

While the panel examined short-term exposure of up to 24 hours to high levels of ozone, Patton said more studies are needed on long-term chronic exposure, where the risk of premature death "may be larger than those observed in acute effects studies alone."

The report said premature deaths from ozone exposure are higher among individuals with lung and heart disease, although such deaths are not restricted to those at high risk of death within a few days.

Based on a review of health studies, the researchers could not determine whether there is a threshold below which no fatalities can be assured from ozone exposure. If such a point exists, however, it is below the ozone levels allowed for public health.

Environmentalists and health advocates have long argued that multiple health studies suggest exposure to smoggy air not only aggravates respiratory problems, but also causes thousands of annual deaths. But in a number of cases, the EPA and the White House OMB, which reviews regulations, have disagreed over the certainty of the link.

Patton said the OMB has sought to minimize the relationship of pollution and premature deaths in reviewing several air pollution regulations, resulting in a lower calculation of health benefits from reducing pollution.

"This has been used by industry to try to attack health standards by minimizing the societal benefits," said Patton.

One case involves the EPA's decision last month to tighten the ozone health standard and reduce the allowable air concentration. The OMB argued in the cost-benefit analysis  that there was "considerable uncertainty" in the association between ozone levels and deaths. As a result, the EPA issued a cost-benefit range from an annual net societal cost of $20 billion to a savings of $23 billion, depending largely on whether the lives saved from ozone-related premature deaths are considered.

In a separate incident involving rulemaking for emissions standards for lawn mowers and other small engines, OMB officials objected to the EPA quantifying ozone-related mortality benefits. In response, the EPA removed "all references to quantified ozone benefits" in the proposed rule, according to an e-mail sent by EPA to the OMB. The small engine regulation is awaiting final action.


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National Academy of Sciences

National Research Council