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Letter Peer Reviews of Exposure and Hazard Information for Five PBT Chemicals

On May 25, 2018, EPA issued a Federal Register notice announcing information on letter peer reviews of EPA’s 1) Exposure and Use Assessment and 2) Human Health and Environmental Hazard Summary for the five persistent, bioaccumulative, and toxic (PBT) chemicals selected for expedited review under the amended Toxic Substances Control Act (TSCA). Learn more about the five PBT chemicals selected for expedited review under TSCA.

Preparatory Virtual Meeting

OnJune 25, 2018, EPA held a prepatory virtual meeting for experts selected to serve as letter peer reviewers to comment on and ask questions regarding the scope and clarity of the draft charge questions to be used in completing their reviews.

Written Comments on Peer Review Documents

Charge questions and other documents  considered by the peer reviewers are available below and in docket EPA-HQ-OPPT-2018-0314. EPA accepted public comments on these documents through August 17, 2018 in docket EPA-HQ-OPPT-2018-0314 on The list of experts is also available below and in the docket.

Additional information may be found in the docket (; docket EPA-HQ-OPPT-2018-0314) or by contacting the Peer Review Leader, Todd Peterson, Ph.D. ( or 202-564-6428).

The final peer review responses to the charge questions are available here.

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