A House panel recently examined efforts by the U.S. Environmental Protection Agency (EPA) to study human exposure to, and toxic effects of, common industrial chemicals. EPA is not assessing enough chemicals and is taking too long to complete the assessments it does undertake, lawmakers said. Witnesses complained that without rigorous scientific studies as a foundation, federal and state agencies cannot set air and water quality standards that protect public health.

The House Science and Technology Committee's Subcommittee on Investigations and Oversight held the hearing June 12. Much of the hearing focused on the Integrated Risk Information System (IRIS), EPA's program for studying toxins. IRIS is a publicly searchable database for studies on the human health effects of hundreds of industrial chemicals and other substances.

Although hundreds of new chemicals appear on the market every year, EPA's pace for completing IRIS assessments has slowed dramatically in recent years, panel members and witnesses said. Ranking Member James Sensenbrenner (R-WI) pointed out that EPA has completed only two IRIS assessments in each of the last two years. He called the process "broken down."

Critics say revisions to the IRIS assessment process, announced April 10, will worsen delays by adding additional steps to the process. One new provision gives other federal agencies, such as the Department of Defense and the Department of Energy, a guaranteed seat at the table during review of EPA's initial assessments.

Sensenbrenner said the new interagency review requirement, managed by the White House Office of Management and Budget (OMB), may further slow the pace of IRIS assessments. "The EPA needs to limit the time frame of assessments to prevent other agencies from indefinitely delaying the process," he said.

Documents released by the subcommittee show EPA experts unhappy with the OMB interagency review period. OMB began wading into the IRIS assessment process in 2004. IRIS program staff said OMB's presence "has added tremendously to the time it takes to release" draft and final assessments.

Giving certain agencies an opportunity to review IRIS assessments also creates a conflict of interest, critics say. The defense industry, including the Pentagon and its contractors, emit more pollution than any other sector. If EPA finds a chemical poses a risk to public health, these agencies may be held liable in court or forced to clean up the pollution.

Controversy surrounding a past IRIS assessment on perchlorate, a chemical found in rocket fuel, could foreshadow future interference by the Pentagon, according to Linda Greer, Director of the Health Program at the Natural Resources Defense Council. "The Defense Department mounted a years-long battle, and elicited White House support, against IRIS draft assessments in 1998 and in 2002 that had determined that even low doses of perchlorate may be harmful to early development of the human brain," Greer said in testimony.

The perchlorate assessment drew the attention of Pentagon officials and defense contractors because it is widely used in defense activity. Public health advocates have pushed for perchlorate regulation because it has been widely detected in public drinking water supplies and is a proven inhibitor of human thyroid functions. Greer said the delay means "the public remains years away from a national drinking water standard that will protect their health."

An IRIS assessment for trichloroethylene, another common contaminant, continues to be delayed. Lenny Siegel, head of the Center for Public Environmental Oversight, testified that the Navy Department has been integral in the long delay.

Witnesses said the defense agencies are able to delay assessments by questioning the scientific certainty of EPA's work and demanding further study be done before the assessment goes forward. These constant claims of uncertainty keep EPA in an interminable quest for more data. Sensenbrenner does not believe complete certainty should be a prerequisite for finalizing an assessment. "Data gaps in risk assessments will always exist, as better science is always developing," he said.

The hearing was the second of two held by the subcommittee examining the revisions to the IRIS assessment process. The first hearing focused primarily on OMB's involvement in IRIS and how that involvement contributes to delay in the assessment process.

Following the first hearing, panel chairman Brad Miller (D-NC) wrote to Susan Dudley, head of OMB's Office of Information and Regulatory Affairs (OIRA), the White House office responsible for coordinating the interagency review. Miller accused OIRA of directly delaying and interfering in IRIS assessments. As with review of agency regulations, Dudley maintains OIRA's role is merely to coordinate the review among executive branch departments. "However, documents that have come to the Subcommittee suggest that OIRA plays a direct role in examining and challenging the science that informs EPA's proposed IRIS entries," Miller wrote.

Miller also criticized the lack of transparency in the revised process for IRIS assessments. Communications among EPA, OMB, and other agencies will be considered "deliberative," according to the document outlining the new process. EPA had hoped to make these back-and-forths among the agencies part of the public record, but OMB persuaded the agency to drop the disclosure policy, according to a recent report by the Government Accountability Office.

"The only reason to hide a discussion about science is if the discussion is actually not about science, but about other things that are being used to trump the science," Miller wrote.