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EPA’S Efforts Endorsed

National Research Council finds agency is improving troubled program on chemical hazard assessment

by Cheryl Hogue
May 19, 2014 | A version of this story appeared in Volume 92, Issue 20

The Environmental Protection Agency’s beleaguered program to assess the hazards of chemicals is on the upswing, the National Research Council (NRC) says.

“Overall, the changes that EPA has proposed and implemented to various degrees constitute substantial improvements” in its Integrated Risk Information System (IRIS), NRC says in a congressionally requested report released this month.

EPA’s chemical hazard assessments include the agency’s scientific judgment on the safe level of exposure to a particular substance. Regulators at EPA, state agencies, and even in foreign governments use these numbers when determining cleanup levels for contamination in air, water, and soil. Consequently, the outcome of an EPA hazard assessment can affect a polluter’s financial liability for cleanup.

Credit: EPA
EPA’s chemical hazard assessments affect the stringency of pollution cleanups, such as removal of sediments contaminated with polychlorinated biphenyls from New York’s Hudson River.
Dredging of PCB-contaminated sediment from the Hudson River, N.Y.
Credit: EPA
EPA’s chemical hazard assessments affect the stringency of pollution cleanups, such as removal of sediments contaminated with polychlorinated biphenyls from New York’s Hudson River.

The program, which has assessed more than 500 chemicals since it was created in 1985, is recognized as providing high-quality assessments, but it suffers from serious flaws.

Environmental and public health activists and some Democrats in Congress have criticized the program for taking years—or, in the case of 2,3,7,8-tetrachlorodibenzo-p-dioxin, more than two decades—to finish an assessment. The chemical industry and some congressional Republicans have faulted the program for lacking scientific credibility. The Government Accountability Office, the investigative arm of Congress, has listed IRIS as a “high risk program” since 2009 because it fails to routinely complete timely, credible chemical assessments.

In a 2011 report highlighting deficiencies in the agency’s draft hazard assessment of formaldehyde, NRC gave unsolicited advice for reform of EPA’s chemical assessment program. Within months, the agency announced a plan for implementing those recommendations. Congress then asked NRC to scrutinize the changes that EPA is making. The recently released NRC report responds to that request.

In addition to a critique of EPA’s progress in updating the chemical assessment program, the report provides further recommendations for improvements. For instance, the report says EPA should check for “risk of bias” in the scientific studies the agency uses in evaluating a chemical’s hazards. This term comes from the field of medicine, particularly clinical studies. Risk of bias involves study characteristics that can introduce systematic errors that lead to incorrect conclusions about the magnitude of observed effects, the report explains. “For example, inadequate randomization (a risk of bias) in a drug study has been associated with overestimates of efficacy measures and underestimates of harm measures,” it says.

The report also recommends that EPA provide technical assistance to public interest and community groups that lack scientific or financial resources, with the aim of helping them provide comments on draft hazard assessments. “Their important perspectives and voices might be less well represented to EPA,” the report says.

That’s because currently, public comments on EPA’s draft assessments overwhelmingly come from industries that make, use, or release the substances, or from government agencies that could be liable for cleanup. “Those stakeholders typically express a concern that scientifically unjustifiably conservative toxicity values will prove costly and provide relatively little additional protection of public health,” the report says. “They often argue for less protective standards or urge more study before assessments are completed.”

Although industry’s views are significant “and its comments are often cogent and constructive,” the report says EPA should receive “the full breadth of perspectives” on chemical hazard assessments.

Lek Kadeli, acting assistant administrator for EPA’s Office of Research & Development, which runs IRIS, says the agency is grateful for the NRC review, its recognition of the progress the agency has made, and the recommendations. EPA says it will convene a workshop later this year to focus on some of the report’s recommendations.

The American Chemistry Council, a chemical industry trade association, says, “We hope that EPA will take quick steps to adopt the recommendations.”

Sen. David Vitter (R-La.), who has castigated EPA’s efforts to assess chemical hazards, says, “Overall, the changes that EPA has proposed show some initial improvements in their chemical assessment process.” He adds, “This is just a first step, and they have a long way to go.”

The report warns that if EPA doesn’t have sufficient funding and staff for the chemical assessment program, it won’t be able to continue the improvements and keep up with scientific advancements.  



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