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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 Webcast Meeting

OnJune 25, 2018, EPA held a prepatory webcast 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

EPA is accepting public comments on the charge questions and other documents to be considered by the peer reviewers. These materials are available below and in docket EPA-HQ-OPPT-2018-0314. Written comments on these materials must be submitted by July 23, 2018 to be considered by the letter peer reviewers. Though the peer reviewers may not be able to fully consider written comments submitted after July 23, 2018, EPA will consider all comments submitted on or before August 17, 2018. Written comments may be submitted to docket EPA-HQ-OPPT-2018-0314 through 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).

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