Toxicity Reexamined

Federal agencies facing cleanup liability will have more opportunities to influence—unduly, critics say—EPA's assessment of health risks from exposures to pollutants under a policy unveiled April 10.

The policy affects entries in EPA's Integrated Risk Information System, which contains EPA's scientific judgment on the safe daily dose for more than 500 substances. Regulators from around the world rely on the database for a variety of decisions that have big financial impacts, such as the degree of cleanup a polluter must undertake at a contaminated site or how much human exposure to a chemical is allowable.

According to EPA, the changes will allow the public and other agencies to have an earlier involvement in chemical assessments and calls for "an even more rigorous scientific peer review" of these documents.

The new policy gives special treatment to chemicals deemed "mission critical" by other federal agencies, such as the military, NASA, or the Department of Energy. EPA says a mission-critical chemical is "an integral component to the successful and safe conduct of an agency's mission in any or all phases of its operations."

If it chooses to do so, a federal agency may take up to 18 months to conduct additional toxicity testing on a substance it considers a mission-critical chemical. EPA would delay completion of its risk review until it gets results of those studies.

For a mission-critical chemical, EPA will cooperate with other agencies to determine the intensity of peer review and the type of scientists needed for that appraisal. This includes a range of options from a contractor-led peer review panel, which generally takes the shortest amount of time, to a critique by EPA's Science Advisory Board, which may take several months. The most intense reviews would be those by the National Academy of Sciences, which can take longer than a year.

"These changes to EPA's risk assessment program are devastating," says Sen. Barbara Boxer (D-Calif.), who chairs the Environment & Public Works Committee. "They put politics before science by letting the White House and federal polluters derail EPA's scientific assessment of toxic chemicals."

Jennifer Sass, a toxicologist with the Natural Resources Defense Council, says the policy will bring the pace at which EPA adds or updates entries in the database "close to a grinding halt." This is because of extra public comment periods EPA has added to the assessment process and because federal polluters have a chance to slow the process down by volunteering to do more research.

Boxer says the Government Accountability Office is investigating the process through which EPA adds or updates entries to the chemical database. GAO, the research arm of Congress, will be issuing a report on its findings soon, she adds.

In addition, Boxer said her committee will conduct an oversight hearing soon on EPA's regulation of chemicals.

The American Chemistry Council did not respond to requests for comments by deadline.