Re-evaluation Decision RVD2020-05, Dimethomorph and Its Associated End-use Products

Pest Management Regulatory Agency
14 February 2020
ISSN: 1925-1025 (PDF version)
Catalogue number: H113-28/2020-5E-PDF (PDF version)

Summary

Table of Contents

• Re-evaluation Decision
• Outcome of Science Evaluation
• Regulatory Decision for Dimethomorph
• Risk Mitigation Measures
• Next Steps
• Other Information
• Appendix I Registered Dimethomorph Products in Canada as of December 2019

Re-evaluation Decision

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

Dimethomorph is a commercial fungicide registered for the management of disease in various vegetable and fruit crops, ginseng, and ornamentals grown under field and greenhouse conditions. Currently registered products containing dimethomorph can be found in the Pesticide Label Search and in Appendix I.

The regulatory approach for the re-evaluation of dimethomorph was first presented in the Proposed Re-evaluation Decision PRVD2019-03, Dimethomorph and Its Associated End-use Products,^{Footnote 1} which underwent a 90-day consultation period ending on 28 July 2019. PRVD2019‑03 proposed continued registration of dimethomorph with certain risk mitigation measures that include new and updated label statements, restricted entry intervals, and buffer zones.

Health Canada received comments relating to the health and environmental assessments. Appendix II of RVD2020-05 (full version) presents a summary of these comments along with responses from Health Canada. The comments and information provided did not result in revisions to the risk assessments or any major changes to the proposed regulatory decision described in PRVD2019-03. A reference list of information used as the basis for the proposed re-evaluation decision is included in PRVD2019-03. References that were unintendedly omitted from the list presented in PRVD2019-03 are provided in Health Canada’s response to comments in Appendix II of RVD2020-05. Appendix IV of RVD2020-05 lists additional information used in the re-evaluation decision presented in this re-evaluation decision.

This document (RVD2020-05) presents the final regulatory decision^{Footnote 2} for the re-evaluation of dimethomorph, including the required risk mitigation measures to protect human health and the environment, along with label amendments required to bring labels to current standards. All products containing dimethomorph that are registered in Canada are subject to this re-evaluation decision.

Outcome of Science Evaluation

Dimethomorph is important for the management of potato late blight tuber rot, and sudden oak death on many high value outdoor, container and field grown ornamental plants in nurseries and landscape plantings, especially considering the limited number of registered alternatives for these diseases. Due to its protectant and antisporulant activity, and lower risk for resistance development, dimethomorph is valued as a rotational product in disease management programs.

With respect to human health, risks are considered acceptable for all dimethomorph uses when used according to the revised label directions.

Dimethomorph enters the environment when used to control moulds on a variety of agricultural food and feed crops and outdoor ornamentals, or when it is present in water discharges from use in greenhouses. When used according to revised label directions, environmental risks associated with the use of dimethomorph are considered acceptable.

Regulatory Decision for Dimethomorph

Health Canada has completed the re-evaluation of dimethomorph. Under the authority of the Pest Control Products Act, Health Canada has determined that continued registration of products containing dimethomorph is acceptable. An evaluation of available scientific information found that uses of dimethomorph products meet current standards for protection of human health and the environment when used according to revised label directions. Label amendments, as summarized below and listed in Appendix III of RVD2020-05, are required. No additional data are required.

Risk Mitigation Measures

Registered pesticide product labels include specific directions for use. Directions include risk mitigation measures to protect human health and the environment and must be followed by law. Required label amendments and mitigation measures resulting from the re-evaluation of dimethomorph are summarized below. Refer to Appendix III of RVD2020-05 for details.

Human Health

Label improvements required to meet current standards include updated statements for personal protective equipment (PPE).

Risk-reduction measures include:

• a label restriction against applications as a mist or fog to protect mixer/loader/applicators,
• updated restricted-entry intervals (REIs) for certain agricultural uses to protect workers entering treated sites,
• and a statement promoting best management practices in order to minimize human exposure and protect bystanders from spray drift.

Residue definition for enforcement:

• The residue definition for the dietary risk assessment and enforcement is expressed as the parent compound, 4-[3-(4-chlorophenyl)-3-(3,4-dimethoxyphenyl)-1-oxo-2-propen-1-yl] morpholine for all food commodities. No change to the current residue definition is required.

Environment

Risk-reduction measures required to protect the environment include:

• hazard statements on the label to inform the user that dimethomorph is toxic to aquatic organisms,
• buffer zones to mitigate the risk of exposure to non-target aquatic organisms,
• a label statement to inform the user to not discharge dimethomorph-contaminated effluent from greenhouses into aquatic environments,
• a label statement informing users of ways to reduce the potential for runoff,
• and a label statement indicating dimethomorph may leach to groundwater.

Next Steps

To comply with this decision, the required mitigation measures must be implemented on all product labels sold by registrants no later than 24 months after the publication date of this decision document. Refer to Appendix I for details on specific products impacted by this decision.

Other Information

Any person may file a notice of objection^{Footnote 3} regarding this decision on dimethomorph within 60 days from the date of publication of RVD2020-05. For more information regarding the basis for objecting (which must be based on scientific grounds), please refer to the Pesticides section of the Canada.ca website (Request a Reconsideration of Decision) or contact the PMRA’s Pest Management Information Service by phone (1-800-267-6315) or by e-mail (pmra.info-arla@hc-sc.gc.ca).

The relevant test data on which the decision is based (as referenced in PRVD2019-03 and RVD2020-05) are available for public inspection, upon application, in the PMRA’s Reading Room (located in Ottawa). For more information, please contact the PMRA’s Pest Management Information Service.

Appendix I Registered Dimethomorph Products in Canada as of December 2019