Key takeaway
What This Development Means
Canada has completed its potassium bicarbonate pesticide re-evaluation, allowing four registered products to remain available subject to amended conditions. New labels must address protective equipment, restricted entry, spray drift, disposal and enclosed-area ultra-low-volume applications. Registrants, retailers and users have until 4 August 2028 to complete the transition safely across Canada.
Is potassium bicarbonate still approved as a pesticide in Canada?
Yes. Health Canada's final re-evaluation found the four registered products acceptable when used under amended conditions. Registrations continue, but labels must incorporate new risk-reduction measures. The products cover two technical ingredients and two commercial fungicides. Users must follow the label attached to their supplied product throughout the 24-month transition period.
What changes are required by 4 August 2028?
Registrants and retailers must complete the transition to amended labels within 24 months of publication. Changes address personal protective equipment, restricted-entry information, spray drift, disposal and enclosed-area ultra-low-volume uses. Those enclosed applications require respirator and ventilation controls. Employers should update assessments, training, stock handling and application procedures before the deadline.
Source basis: Health Canada PMRA, Re-evaluation Decision RVD2026-04 (4 August 2026)
Health Canada's Pest Management Regulatory Agency published its final re-evaluation of potassium bicarbonate on 4 August 2026. The Canada potassium bicarbonate decision allows four pesticide registrations to continue, but requires label amendments addressing worker protection, restricted entry, spray drift, disposal and some enclosed-area applications. Registrants, retailers and users have 24 months to transition.
Potassium bicarbonate is a contact fungicide used on greenhouse and field crops, including grapes, apples, cannabis and hemp. The authority concluded that registered uses remain acceptable under amended conditions. No amendment, withdrawal or superseding decision had been identified by 7 August.
Worker Protection And Application Controls
Required label changes include updated personal protective equipment and restricted-entry information. For ultra-low-volume application in enclosed areas, labels must specify respirator and ventilation controls for all labelled crops. Spray-drift and disposal directions will also be revised.
The Canada potassium bicarbonate decision makes these controls mandatory on amended labels. These conditions matter beyond farms. Formulators, distributors, greenhouse operators and agricultural contractors need aligned labels, stock controls, training and application procedures. Employers should compare existing risk assessments with the final requirements and ensure workers understand when respiratory protection and ventilation are necessary.
Four Registrations Remain Under Amended Conditions
The decision identifies two technical products and two commercial products: MilStop Technical, Potassium Bicarbonate Technical, MilStop Foliar Fungicide and Potassium Bicarbonate. Registrations range from 85% commercial soluble powder to 100% technical or soluble-granule formulations.
All required mitigation measures and label updates must be implemented on product labels no later than 24 months after publication, corresponding to 4 August 2028. The period applies to registrants and retailers moving to products bearing amended labels, while users must follow the updated directions once transitioned products are supplied. Health Canada's amendment-timeframe section refers once to PRVD2026-04. This is a typographical inconsistency: the final decision is RVD2026-04, and the preceding proposed decision was PRVD2025-06.
The Canada potassium bicarbonate decision therefore preserves registrations while changing the conditions of sale and use.
The Canada potassium bicarbonate decision also permits any person to submit a scientifically supported Notice of Objection within 60 days of the 4 August 2026 publication date. Health Canada states the 60-day period but does not print a separate closing date.
Actions For The Pesticide Supply Chain
Registrants should prepare label amendments and production changeovers, then communicate timing to distributors. Retailers should segregate old and updated inventory where necessary and avoid selling beyond permitted transition arrangements. Users should confirm which label accompanies each container rather than relying on previous practice.
Growers and contractors using ultra-low-volume equipment indoors should prioritise respiratory and ventilation reviews. Advisers can help translate the Canada potassium bicarbonate decision into site-specific procedures, training and records. Early coordination will reduce the risk of mismatched labels, unsafe applications or stranded stock as the 2028 deadline approaches.
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