December 4, 2008

Panel Seeks Changes in E.P.A. Reviews

http://www.nytimes.com/2008/12/04/science/04epa.html?_r=1&th&emc=th

By CORNELIA DEAN

The Environmental Protection Agency must revise its approach to assessing environmental health hazards and other risks, because current practices hinder useful and timely regulation, an expert panel of The National Research Council says.

The council, the research arm of the National Academy of Sciences, said the agency should scrap some of the assumptions on which its decisions have been based and reduce its focus on individual chemicals and other hazards to consider how they act in combination. It should also accept that uncertainty was always an issue and seek to provide practical information to policy makers as quickly as possible.

The report, which the panel produced at the behest of the E.P.A., was made public Wednesday and is online at www.nas.edu.

Determining whether something is a hazard and, if so, how great and to whom is a crucial step in devising appropriate environmental regulations, the panel said, and the field is advancing as testing systems and other technology advance.

But assessing environmental risks is highly complex and full of uncertainty, it continued, and at the E.P.A., "the regulatory risk-assessment process is bogged down," with some assessments taking a decade or more. For example, the report cited an assessment of trichloroethylene, a commonly used solvent, that has been under way since the 1980s and is not expected before 2010.

The environmental agency's conclusions about risk are usually crucial in establishing regulatory goals. As a result, they are often subject to intense political or economic pressure. When the Bush administration proposed changes that it said would streamline risk-assessment procedures, critics called the proposal an effort to weaken environmental regulation. In a 2007 report, the academy dismissed the proposal as "fundamentally flawed," and it was withdrawn.

Thomas A. Burke, an epidemiologist at the Bloomberg School of Public Health at Johns Hopkins University, said the new report focused on the use of "defaults," assumptions that are made about one factor or another in the face of uncertainty.

"Many of them are founded on good science," he said, "but there are some hidden assumptions. Right now, when we don't have information on a pollutant, we treat it as if there's no risk. That's a so-called hidden default."

Dr. Burke added, "We really need to address these gaps."

Another issue the report cited was the effect of cumulative exposures to a variety of environmental hazards. Usually these hazards are studied one by one. But Dr. Burke said, "You have to consider not just the one compound but you have to ask broadly, because people are exposed to many, many thousands of substances."

A spokesman for the American Chemical Society said it would have no comment on the report until members had had time to read it.

Joel Tickner, a professor of environmental health at the University of Massachusetts at Lowell who studies chemicals in the environment, said that while he had not seen the report, its focus on speeding environmental review and consideration of cumulative effects was overdue.

"We put a lot of effort into finding more complex ways to characterize the problems while we don't put nearly as much resources into studying solutions," Professor Tickner said.

He, too, cited trichloroethylene, saying, "Given that we know trichloroethylene is a neurotoxin and a carcinogen and that there are very good alternatives, it makes no sense to put so much resources into studying it."

Professor Tickner said that by focusing on safer alternatives for processes like degreasing, industries in Massachusetts had reduced their use of the compound by 90 percent.

"But as long as we are uncertain, we assume there is no problem," he said. "That provides almost an incentive to having scientific uncertainty."