Proposed re-evaluation decision PRVD2024-05, 3-methyl-2-cyclohexen-1-one and its associated end-use products

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Pest Management Regulatory Agency
24 September 2024
ISSN: 1925-0967 (PDF version)
Catalogue number: H113-27/2024-5E-PDF (PDF version)

Summary

Table of contents

• Proposed re-evaluation decision for 3-methyl-2-cyclohexen-1-one and associated end use products
• Key risk-reduction measures
• Next steps
• Other information
• Additional scientific information

Proposed re-evaluation decision for 3-methyl-2-cyclohexen-1-one and associated end use products

Under the Pest Control Products Act, all registered pesticides must be re-evaluated regularly by Health Canada's Pest Management Regulatory Agency (PMRA) to ensure that they continue to meet health and environmental safety standards and continue to have value. The re-evaluation considers data and information from various sources such as information from pesticide manufacturers, incident reports, and other regulatory agencies. Health Canada applies internationally accepted risk assessment methods, risk management approaches and policies to all re-evaluations.

This document (Proposed Re-evaluation Decision PRVD2024-05, 3-Methyl-2-cyclohexen-1-one and Its Associated End-use Products) presents the proposed regulatory decision for the re-evaluation of 3-methyl-2-cyclohexen-1-one (also referred to as methylcyclohexenone), including any proposed amendments (risk mitigation measures) to protect human health and the environment, as well as the science evaluation on which the proposed decision is based.

Methylcyclohexenone is an anti-aggregation pheromone (semiochemical) registered as an insect repellent to deter Douglas-fir beetle, Dendroctonus pseudotsugae, and spruce beetle, Dendroctonus rufipennis, from attacking Douglas-fir trees and spruce trees, respectively. Methylcyclohexenone is a naturally occurring pheromone produced by beetles (Dendroctonus sp.),and released after they successfully attack a host tree.

There are three commercial class end-use products containing methylcyclohexenone registered in Canada which are formulated as slow-release generators contained in individual bubble caps or dispensers. The product is applied at least two weeks prior to the expected attack flight of beetles by manually stapling individual bubble caps/dispensers to trees and stumps at a minimum height of 2.5 metres above ground. Currently registered products containing methylcyclohexenone can be found in the Pesticide Product Information Database and in Appendix I of the full version of PRVD2024-05.

Methylcyclohexenone has a non-toxic mode of action and is of value in providing a pest management solution. Based on the current use pattern of methylcyclohexenone, dietary exposure (food and drinking water) to methylcyclohexenone is not anticipated. The potential health (occupational, residential, and bystander) and environmental risks are considered to be acceptable when products containing methylcyclohexenone are used according to the current label directions. As a result of re-evaluation, no additional mitigation measures are proposed, however, updates to standard label statements as per current labelling standards are proposed (Appendix II of PRVD2024-05).

Key risk-reduction measures

Human health

• Update personal protective equipment to current standards.

Environment

• Update environmental precautions for aquatic environment and disposal.

Under the authority of the Pest Control Products Act and based on an evaluation of currently available scientific information, products containing methylcyclohexenone (Appendix I of PRVD2024-05) are being proposed for continued registration in Canada, with the proposed updates to label statements (Appendix II of PRVD2024-05).

This proposed re-evaluation decision is a consultation document and is subject to a 90-day public consultation period^{Footnote 1}. Please forward any comments to PMRA Publications. All products containing methylcyclohexenone that are registered in Canada are subject to this proposed re-evaluation decision.

Refer to Appendix I of PRVD2024-05 for details on specific products impacted by this proposed decision.

Next steps

Upon publication of this proposed re-evaluation decision, the public, including the registrants and stakeholders are encouraged to submit comments during the 90-day public consultation period.

Health Canada will accept written comments on this proposal up to 90 days from the date of publication of this document. Before making a re-evaluation decision on methylcyclohexenone, the comments received during the consultation period will be taken into consideration in preparation of re-evaluation decision document, which could result in revised risk mitigation measures. A science-based approach will be applied in making a final decision on methylcyclohexenone. Health Canada will then publish a final re-evaluation decision document, which will include the decision, the reasons for it, a summary of comments received on the proposed re-evaluation decision, and Health Canada's response to these comments.

Other information

When Health Canada makes its re-evaluation decision, it will publish a Re-evaluation Decision on 3-methyl-2-cyclohexen-1-one (based on the Science evaluation of PRVD2024-05). In addition, the test data referenced in this consultation document will be available for public inspection, upon application, in the PMRA's Reading Room.

Additional scientific information

Additional scientific data are not required at this time.