February 18, 2021

EPA to Update "Systematic Review" Approach for Chemical Risk Evaluations

EPA is updating its approach to “systematic review,” its method of selecting and reviewing scientific studies used to inform chemical risk evaluations under the Toxic Substances Control Act (TSCA), the agency announced on Feb. 16. As amended by the 2016 Frank R. Lautenberg Chemical Safety for the 21st Century Act, TSCA requires EPA’s Office of Pollution Prevention and Toxics (OPPT) to establish a process for risk evaluation and to complete chemical risk evaluations under strict deadlines. EPA’s announcement coincides with the publication of a report by the National Academies of Sciences, Engineering, and Medicine that recommends changes to the agency’s systematic review process to ensure that it is “comprehensive, workable, objective, and transparent.”

EPA’s “Application of Systematic Review in TSCA Risk Evaluations” document, which was released in 2018, is the subject of the National Academies peer review. The National Academies committee found that EPA’s approach to systematic review did not adequately meet “the state of the practice,” or how the steps of systematic review—problem formulation and protocol development, evidence identification, evidence evaluation, evidence synthesis, and evidence integration—are generally conducted. The report urges EPA to “comprehensively reevaluate” its methods. According to the agency’s news release, EPA is already developing a TSCA systematic review protocol that addresses recommendations in the National Academies report.

According to the National Academies, OPPT can improve its use of systematic review by participating in cross-sector efforts to develop and validate new tools and approaches for areas where systematic review is applied, such as exposure and environmental health. The report also encourages EPA to consider how existing approaches to hazard assessment—like methodologies from the National Institute of Environmental Health Science’s Office of Health Assessment and Translation and EPA’s own Integrated Risk Information System and Navigation Guide—could be incorporated into its systematic review process. Another recommendation is intended to make the documentation of EPA’s process more transparent and easier to follow: the National Academies urges OPPT to assemble a handbook for TSCA review and evidence integration methodology that details the steps in its process.

EPA expects to publish its updated TSCA systematic review protocol later this year and states that it intends to adopt many of the National Academies’ recommendations. The agency will take public comment on its updated approach at that time.

For more information, see the news release from the National Academies or download a PDF of the report from the National Academies Press.