Chlorpyrifos Update
May 8-9, 2019 Pesticide Program Dialogue Committee Meeting
•	Chlorpyrifos has been a widely used pesticide since 1965. Since its first registration,
chlorpyrifos has been reviewed by EPA for tolerance reassessment and reregi strati on. It
is currently undergoing a registration review that must be completed before October
2022.
•	In March 2017, EPA denied a 2007 petition that asked the Agency to revoke all pesticide
tolerances and registrations for chlorpyrifos. EPA concluded that despite several years of
study the science addressing neurodevelopmental effects requires further evaluation.
•	On August 9, 2018, the Ninth Circuit issued a decision vacating EPA's 2017 order
maintaining a tolerance for the pesticide chlorpyrifos and remanding to the EPA with
directions to revoke all tolerances and cancel all registrations for chlorpyrifos within 60
days of the issuance of the court's mandate.
•	The U.S. Court of Appeals for the Ninth Circuit agreed to re-hear its decision in this
matter. Oral argument occurred March 26, 2019.
•	On April 19, 2019, the Court ordered EPA to make a full and final decision on the
objections associated with the March 2017 denial within 90 days.

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