National Academies Committee Recommends EPA Improve Its Use of Systematic Review in TSCA Risk Evaluations; EPA “Commits to Strengthening Science Used in Chemical Risk Evaluations”
By Lynn L. Bergeson and Carla N. Hutton
On February 16, 2021, the National Academies of Sciences, Engineering, and Medicine (National Academies) announced the availability of a report entitled The Use of Systematic Review in EPA’s Toxic Substances Control Act Risk Evaluations. The U.S. Environmental Protection Agency (EPA) requested that the National Academies convene a committee to review EPA’s 2018 guidance document on Application of Systematic Review in TSCA Risk Evaluations and associated materials. In its final report, the Committee to Review EPA’s Toxic Substances Control Act (TSCA) Systematic Review Guidance Document states that it “was in strong consensus that the processes used by [the Office of Pollution Prevention and Toxics (OPPT)] do not meet the evaluation criteria specified in the Statement of Task (i.e., comprehensive, workable, objective, and transparent).” The Committee recognizes the “substantial challenges in implementing review methods on the schedule required by” the Frank R. Lautenberg Chemical Safety for the 21st Century Act (Lautenberg Act), but concluded that those challenges “have not yet been successfully met.” The final report includes the following summary of the Committee’s general recommendations:
- OPPT’s approach to systematic review does not adequately meet the state of the practice. The Committee suggests that OPPT comprehensively reevaluate its approach to systematic review methods, addressing the comments and recommendations provided in Chapter 2 of the final report.
- With regard to hazard assessment for human and ecological receptors, the Committee comments that “OPPT should step back from the approach that it has taken and consider components” of the Office of Health Assessment and Translation (OHAT) of the National Toxicology Program, EPA’s Integrated Risk Information System (IRIS), and Navigation Guide methods that could be incorporated directly and specifically into hazard assessment.
- The Committee finds that OPPT’s use of systematic review for the evidence streams, for which systematic review has not been previously adapted, “to be particularly unsuccessful.” The Committee suggests that OPPT elaborate plans for continuing the refinement of methods, ideally in collaboration with internal and external stakeholders. The Committee also suggests that OPPT evaluate how the existing OHAT, IRIS, and Navigation Guide methods could be modified for the other evidence streams. In addition, according to the Committee, OPPT should use existing EPA guidance, such as the Guidelines for Human Exposure Assessment, the Guidelines for Ecological Risk Assessment, and the operating procedures for the use of the ECOTOXicology knowledgebase (ECOTOX). Following these existing guidelines would improve transparency of the assessments.
- The Committee recommends that EPA put together a handbook for TSCA review and evidence integration methodology that details the steps in the process. Throughout the final report, the Committee points to problems of documentation. The Committee “believes that the effort of developing and publicly vetting a handbook will pay off in the long run by making the process more straightforward, transparent, and easier to follow.”
The final report states that “[t]here is an ongoing cross-sector effort to develop and validate new tools and approaches for exposure, environmental health, and other new areas of application of systematic review,” and the Committee “strongly recommends that OPPT staff engage in these efforts.” According to the final report, the approaches used for TSCA evaluation “would benefit from the substantial external expertise available,” as well as additional transparency and acceptance by the different stakeholders as these tools are developed.
EPA published a press release on February 16, 2021, in response to the Committee’s report, announcing that it “will refine its approach to selecting and reviewing the scientific studies that are used to inform” TSCA chemical risk evaluations. According to EPA, its “ongoing effort to update its systematic review approach” is also part of its “broader efforts” to review the first ten TSCA risk evaluations. EPA states that it “is not using, and will not again use, the systematic review approach that was reviewed by the Academies.” The 2018 Application of Systematic Review document “represented EPA’s practices at that time.” According to the press release, EPA has already begun to develop a TSCA systematic review protocol in collaboration with its Office of Research and Development to incorporate approaches from the IRIS Program. EPA “expects to publish and take public comment on a TSCA systematic review protocol that will adopt many of the recommendations in the Academies’ report later this year.”