Response to comments received on the consultation for proposed maximum residue limits for fluoxapiprolin (PMRL2025-20)
Health Canada
Pesticides Regulatory Directorate
Healthy Environments and Consumer Safety Branch
18 June 2026
Health Canada published the Proposed Maximum Residue Limit PMRL2025-20, Fluoxapiprolin, for a 75-day public consultation period ending on 26 November 2025. Health Canada proposed several new maximum residue limits (MRLs) for fluoxapiprolin on various food commodities. Comments were received from the public and non-government organizations.
Some comments questioned the hazard characterization and selection of Toxicology Reference Values (TRVs), environmental and value assessments, and perceived procedural violations. Other comments expressed concern about the use of pesticides on food and animal testing.
Health Canada acknowledges receipt of these comments. Please note that Health Canada's PMRL consultation process is intended to obtain comments on the scientific information which form the basis of the proposed MRL decisions. As these are based on residue chemistry data and dietary exposure assessments, all comments not related to this information are considered out of scope and will not be addressed. Responses to all MRL and dietary exposure assessment-related comments are presented below. The comments received do not change the scientific basis of the proposed MRLs, in turn these MRLs will be specified in the MRL database. More information on MRLs can also be found on the Maximum residue limits, human health, and food safety webpage.
Comment
One commenter expressed concern regarding the uncertainty of fluoxapiprolin MRLs for green onions, bulb onions and cucumber.
Health Canada response
An MRL is not a measure of the toxicity of a pesticide. It is a scientifically-based calculation that estimates the maximum potential concentration of residues on food commodities, when a pesticide was used according to approved label directions. Health Canada establishes MRLs only when there are no health risks of concern to consumers.
Health Canada uses a statistical MRL calculation tool, adopted internationally by Organisation for Economic Co-operation and Development (OECD) countries and regulatory authorities, such as the European Union, to calculate MRLs. Health Canada scientists collaborated with other OECD scientists to develop this OECD calculator. The calculator is also used by the Joint Food and Agriculture Organization (FAO)/World Health Organization (WHO) Meeting on Pesticide Residues (JMPR) to recommend MRLs for adoption by the Codex Committee on Pesticide Residues (CCPR) to protect consumer health and promote fair practices in food trade.
This MRL calculation tool is based on the highest potential amount of residue that may remain on crops when a pesticide is used according to label directions. The calculator compares the lowest residue with the highest residue; the larger the range is, the greater the difference present in the data. This difference is taken into account when computing the MRL and may lead, in some cases, to MRL proposals considerably greater than the highest residue observed in the trials. This helps ensure MRLs are not underestimated when the product is used in different regions or growing conditions.
The OECD White Paper, which explains this Calculator, notes that for smaller datasets (i.e., less than 10 points), the MRL proposed is typically greater than the highest residue in the data set to ensure that the MRL is not underestimated. For such residue datasets, this outcome is expected, especially when there is a great deal of variability within the data set.
Comment
One commenter reported the lack of an adequate dietary risk assessment and that only a qualitative assessment was conducted since no toxicology reference values were established.
Health Canada response
As reported in the Tables 3 and 4 of Appendix I in the Proposed Registration Decision PRD2025-07, Fluoxapiprolin and Xivana Prime, Toxicology Reference Values (TRVs) were established for fluoxapiprolin as well as its metabolite Fluoxapiprolin-BDM-pyrazole (BCS-BP32808). Quantitative dietary risk assessments were conducted using these TRVs, and results were summarized in Table 15 of Appendix I of PRD2025-07, where it was concluded that dietary risks from food and drinking water were not of health concern.
Comment
The same commenter noted the lack of Codex MRLs for fluoxapiprolin and misalignment of certain proposed MRLs with those proposed by the United States.
Health Canada response
At the time the Proposed Registration Decision (PRD) document was prepared, Codex had not yet published its decision on fluoxapiprolin MRLs. Since then, fluoxapiprolin MRLs were discussed and adopted at the 56th session of the Codex Committee on Pesticide Residues (CCPR) and can now be found on the Codex Alimentarius Pesticide Index webpage.
As noted in Appendix II of the PRD2025-07, US tolerances for strawberries and animal matrices were not established as these were exempt from the requirement of a tolerance, under the Code of Federal Regulations, since there are no expectations of measurable residues. Health Canada does not have such an authority under the Food and Drugs Act, therefore the Canadian MRLs were proposed at the method limit of quantitation.
Conclusion
Dietary risks from the consumption of fluoxapiprolin residues in or on various crops were shown to be acceptable when fluoxapiprolin is used according to the approved label directions. As such, the foods containing these residues are safe to eat, and the MRLs will be specified in the MRL database as proposed in PMRL2025-20.