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IRIS

IRIS and the National Research Council (NRC)

NAS Workshop to Discuss Strategies and Tools for Searching, Screening, Evaluating, and Integrating Mechanistic Data in Chemical Assessments (December 2018)

Mechanistic data are a rich source of information that is increasingly becoming a large component of the evidence used to inform human health risk assessments. Mechanistic studies, which include a variety of designs (i.e., in vitro, in vivo using various routes of exposure, ex vivo, and in silico), report measurements related to a health outcome that inform the biological or chemical events associated with phenotypic effects in both mammalian and non-mammalian model systems. This information can help to identify adverse outcomes associated with chemical exposures, including those that may not be typically evaluated in animal bioassays or human studies.

These studies can also guide the evaluation of the relevance of animal data to human health risk assessment. Despite the importance of considering mechanistic data, incorporation of these studies within a systematic review framework remains challenging. Challenges include: screening large numbers of diverse studies efficiently; developing transparent and reproducible criteria for identifying the most informative mechanistic studies; the lack of well-developed systematic review tools to assess internal validity of in vitro and in silico studies; and underdeveloped structured frameworks to guide integration of mechanistic information with human and animal health effects evidence.

The overall aim of this workshop is to explore the strategies and tools that are being developed across the systematic review community to search, screen, evaluate, and incorporate mechanic information into structured approaches for evidence synthesis and integration.

NRC Workshop to Discuss Advances Made to the IRIS Program (Feb 2018)

A committee of the National Academies of Sciences (NAS) hosted a public workshop on February 1-2, 2018, in Washington, D.C., to review systematic review and other method advances made by EPA in its Integrated Risk Information System (IRIS) Program.

In 2014, the NAS published a report evaluating the IRIS process. The NAS noted that the IRIS Program had made “substantial improvements” and provided recommendations in a report, Review of EPA’s Integrated Risk Information System [IRIS] Process.

Since 2014, the IRIS Program has continued to make advances in implementing systematic review, and has improved approaches for conducting dose-response analysis to further address recommendations provided by the NAS. EPA requested the NAS convene a panel to evaluate these recent advancements and develop a report for EPA.

During the workshop, the NAS heard from EPA and the public. Workshop topics focused on how IRIS has addressed the 2014 NAS recommendations, including approaches for evidence identification, evidence evaluation, and evidence integration, as well as advances in quantitative methods. The NAS panel has developed a report based on information presented by EPA at the workshop included below:

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IRIS Workshop to Discuss the NRC Recommendations (October 2014)

EPA hosted a public workshop on October 15-16, 2014 to discuss recommendations from the National Academies' National Research Council's May 2014 report on ways to further improve the scientific quality of IRIS assessments. In their report, the NRC commended EPA for its substantive new approaches, continuing commitment to improving the process, and successes to date.

As a result, EPA announced an agreement with the National Academies’ National Research Council (NRC) to arrange for independent experts to attend the IRIS bimonthly public meetings, in order to provide input on the science underlying the development of IRIS assessments through participation in IRIS Public Science Meetings.

These independent experts, speaking on their own behalf, attended the IRIS meetings to contribute to the scientific discussions of issues amongst EPA, stakeholders, and the public. The first meeting where NRC identified experts were invited to join the public discussion on key science questions and preliminary assessment materials was the February 2015 IRIS Public Science meeting. The February 2015 meeting agenda, listed under meeting materials, specifies the discussants that were identified by the NRC.


NRC Review of the IRIS Assessment Development Process (May 2014)

The National Academies’ National Research Council (NRC) released their review of the IRIS assessment development process. The NRC report applauded EPA’s efforts to improve IRIS and found that the Program had moved forward steadily in planning for and implementing changes in each element of the assessment process.

While recognizing EPA was still implementing changes, they noted that, “overall, the committee expects that EPA will complete its planned revisions in a timely way and that the revisions will transform the IRIS program.” Their report noted that the IRIS Program had made substantial progress in a short time, and the committee offered recommendations that build on EPA’s progress.

These recommendations provide continued direction for further improving the IRIS Program.

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NRC Recommendations (April 2011)

The National Research Council (NRC) offered recommendations to the EPA for improving the development of IRIS assessments in their Review of the Environmental Protection Agency’s Draft IRIS Assessment of Formaldehyde, these recommendations went beyond this report and helped influence the entire IRIS process for developing assessments.

EPA Response

EPA submitted materials to the NRC to support their review of the IRIS assessment development process and implementation of improvements responsive to the 2011 NRC recommendations: