Proposed re-evaluation decision PRVD2026-05, Ozone and its associated end-use products

Health Canada
Healthy Environments and Consumer Safety Branch
Pesticides Regulatory Directorate
21 October 2026
ISSN: 1925-0967 (PDF version)
Catalogue number: H113-27/2026-5E-PDF (PDF version)

Summary

Table of contents

• Proposed re-evaluation decision for ozone and its associated end-use products
• Next steps
• Other information
• Additional scientific information

Proposed re-evaluation decision for ozone and its associated end-use products

Under the authority of the Pest Control Products Act, all registered pesticides must be regularly re-evaluated by Health Canada 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 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.

Ozone is a soluble gas that, when dissolved in water, functions as a powerful oxidizing agent and a broad-spectrum antimicrobial. Ozone is used to control zebra mussels in water intake systems and as a sanitizing/disinfecting agent for hard non-porous surfaces, including food contact surfaces. Aqueous ozone kills bacteria and fungi by damaging the cytoplasmic membrane through ozonolysis and also by oxidation of proteins which leads to a loss of organelle function. It kills molluscs (zebra mussels) by oxidation of organic matter which leads to toxic and lethal effects.

There are no manufacturing concentrates or technical actives registered. One restricted-class and one commercial-class ozone generating device are registered. Currently registered products can be found in the Pesticide Product Information Database and in Appendix I of the full version of Proposed Re-evaluation Decision PRVD2026-05, Ozone and its associated end-use products.

This document (PRVD2026-05) presents the proposed re-evaluation decision for ozone and the Science evaluation on which the proposed decision is based. All products containing ozone that are registered in Canada under the Pest Control Products Act are subject to this proposed re-evaluation decision. PRVD2026-05 is subject to a 90-day public consultation period,^{Footnote 1} during which the public (including the pesticide manufacturers and stakeholders) may submit written comments to the Pesticides Publications Section . The final re-evaluation decision will be published after taking into consideration the comments received during the consultation period that are directly related to this proposed re-evaluation decision.

Health Canada, under the authority of the Pest Control Products Act, has conducted all evaluations considered necessary with respect to the health and environmental risks and value of ozone based on available scientific information in accordance with subsection 16(6) of the Pest Control Products Act. Health Canada is proposing for public consultation, pursuant to section 28 of the Pest Control Products Act, the continued registration of ozone and associated end-use products registered for sale and use in Canada under section 21 of the Pest Control Products Act.

Based on the current use pattern of ozone, the potential dietary, occupational, residential, and environmental risks are considered to be acceptable when the registered ozone-generating devices are used according to operating instructions and label directions. As a result of this re-evaluation, no additional mitigation measures are proposed.

Next steps

Upon publication of this proposed re-evaluation decision, the public, including 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 PRVD2026-05. Comments on the proposed decision can be submitted during the consultation period to Health Canada through Pesticides Publications Section, or the Public Engagement Portal (Public Engagement Forms - Consultation Comment). For more information or if you have questions, contact the Pesticides Information Service .

Before making a re-evaluation decision on ozone under section 21 of the Pest Control Products Act, the comments received during the consultation period that are directly related to this proposed decision, such as comments directed to the science evaluation, will be taken into consideration in preparation of the final re-evaluation decision document. A science-based approach will be applied in making a final decision on ozone. In accordance with subsection 28(5) of the Pest Control Products Act, Health Canada will then publish a final re-evaluation decision document, which will include the decision, the reasons for it, a summary of the comments received directly related to the proposed re-evaluation decision during the consultation period, and Health Canada’s response to these comments.

Refer to Appendix I of PRVD2026-05 for details on specific products impacted by this proposed decision.

Other information

The relevant confidential test data on which the proposed decision is based (as referenced in the References Section of PRVD2026-05) are available for public inspection, upon application, in the Pesticides Regulatory Directorate’s Reading Room. For more information, please contact the Pesticides Information Service.

Additional scientific information

No additional scientific data are being requested at this time.