Re-evaluation Note REV2021-02, Update on the Re-evaluation of Chlorpyrifos


On 21 December 2021, Health Canada issued a Re-evaluation Note (REV2021-04, Cancellation of remaining chlorpyrifos registrations under paragraph 20(1)(a) of the Pest Control Products Act). This new document supersedes, and therefore replaces, the Re-evaluation Note (REV2021-02, Update on the Re-evaluation of Chlorpyrifos) published 13 May 2021.

Pest Management Regulatory Agency
13 May 2021
ISSN: 1925-0649 (PDF version)
Catalogue number: H113-5/2021-2E-PDF (PDF version)

Under the re-evaluation program, Health Canada's Pest Management Regulatory Agency (PMRA) has reviewed chlorpyrifos and its associated uses and implemented several risk reduction measures over the years. In 2000, Health Canada removed all residential uses from chlorpyrifos labels. In addition, Health Canada implemented mitigation measures in 2007 (REV2007-01, Update on the Re-evaluation of Chlorpyrifos) to further protect human health and the environment, following an assessment on agricultural and forestry uses. In 2007 (REV2007-01), it was also indicated that an update to the environmental risk assessment for chlorpyrifos would be required.

In December 2020, Health Canada published a re-evaluation decision (RVD2020-14, Chlorpyrifos and Its Associated End-use Products (Environment)) based on an updated environmental risk assessment (PRVD2019-05, Chlorpyrifos and Its Associated End-use Products: Updated Environmental Risk Assessment). In this decision, Health Canada cancelled almost all agricultural uses due to environmental risks of concern while a few uses were acceptable from the environmental perspective. Cancelled uses/products were to be phased out by 10 December 2023, while two cancelled uses (canola for alfalfa looper and garlic for darksided and redbacked cutworm) were granted an extended phase-out period to December 2024 due to the lack of suitable alternatives with the implementation of additional risk mitigation measures.

Health Canada also informed the public in December 2020 (RVD2020-14) that the human health aspect of chlorpyrifos would be updated based on the additional information generated internationally since our last assessment, and that this update would be presented in a future publication. In order to proceed with the update to the human health risk assessment, Health Canada issued a data call-in notice under paragraph 19(1)(a) of the Pest Control Products Act. Registrants of chlorpyrifos failed to satisfy the data requirements. Consequently, Health Canada has cancelled all chlorpyrifos uses/products, including those that remained registered following the environmental risk assessment, in accordance with paragraph 20(1)(a) of the Pest Control Products Act. The existing stocks of all chlorpyrifos products in Canada are being phased out with the following timelines:

The intended work to update the human health assessment is no longer needed as all pest control products containing chlorpyrifos are being cancelled due to failure to satisfy requested data requirements. On this basis, the re-evaluation for chlorpyrifos is now considered complete.

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