Proposed Maximum Residue Limit PMRL2021-27, Sethoxydim
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Pest Management Regulatory Agency
20 July 2021
ISSN: 1925-0843 (PDF version)
Catalogue number: H113-24/2021-27E-PDF (PDF version)
Under the authority of the Pest Control Products Act, Health Canada’s Pest Management Regulatory Agency (PMRA) has concluded that the addition of a new use on basil to the product label of POAST ULTRA Liquid Emulsifiable Herbicide, containing technical grade sethoxydim, is acceptable. The specific uses approved in Canada are detailed on the label of POAST ULTRA Liquid Emulsifiable Herbicide, Pest Control Products Act Registration Number 24835.
The evaluation of this sethoxydim application indicated that the end-use product has value and the human health and environmental risks associated with the new use are acceptable.
Before registering a pesticide for food use in Canada, the PMRA must determine the quantity of residues that are likely to remain in or on the food when the pesticide is used according to label directions and that such residues will not be a concern to human health. This quantity is then legally established as a maximum residue limit (MRL). An MRL applies to the identified raw agricultural food commodity as well as to any processed food product that contains it, except where separate MRLs are specified for the raw agricultural commodity and a processed product made from it.
To comply with Canada’s international trade obligations, consultation on the proposed MRLs is also being conducted internationally by notifying the World Trade Organization, as coordinated by the Canada’s Notification Authority and Enquiry Point.
The proposed MRLs, to be added to the MRLs already established for sethoxydim, are as follows.
|Common name||Residue definition||MRL (ppm)Table 1 Footnote 1||Food commodity|
|Sethoxydim||2-[1-(ethoxyimino)butyl]-5-[2-(ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-one, including metabolites containing the cyclohexen-2-one moiety, (expressed as parent equivalents)||20||Dried basil leaves|
|8.0||Fresh basil leaves|
MRLs established in Canada may be found using the Maximum Residue Limit Database on the Maximum Residue Limits for Pesticides webpage. The database allows users to search for established MRLs, regulated under the Pest Control Products Act, both for pesticides or for food commodities.
International situation and trade implications
The MRLs proposed for sethoxydim in Canada are the same as corresponding American tolerances as listed in the Electronic Code of Federal Regulations, 40 CFR Part 180, by pesticide. Currently, there are no Codex MRLsFootnote 1 listed for sethoxydim in or on any commodity on the Codex Alimentarius Pesticide Index webpage.
The PMRA invites the public to submit written comments on the proposed MRLs for sethoxydim up to 75 days from the date of publication of this document. Please forward your comments to Publications. The PMRA will consider all comments received before making a final decision on the proposed MRLs. Comments received will be addressed in a separate document linked to this PMRL. The established MRLs will be legally in effect as of the date that they are entered into the Maximum Residue Limit Database.
Summary of field trial data used to support the proposed maximum residue limits
Residue data for sethoxydim in basil (fresh and dried) were submitted to support the domestic use of POAST ULTRA Liquid Emulsifiable Herbicide on basil.
Maximum residue limits
The recommendation for maximum residue limits (MRLs) for sethoxydim was based upon the submitted field trial data, and the guidance provided in the OECD MRL Calculator. Table A1 summarizes the residue data used to calculate the proposed MRLs for dried basil leaves and fresh basil leaves.
|Commodity||Application method/ Total application rate
(g a.i./ha)Table a1 Footnote 1
|Preharvest interval (days)||Lowest average field trial residues
|Highest average field trial residues
|Fresh basil||Foliar application/
|Dried basil||Foliar application/
Following the review of all available data, MRLs as proposed in Table 1 are recommended to cover residues of sethoxydim. Residues of sethoxydim in these crop commodities at the proposed MRLs will not pose an unacceptable risk to any segment of the population, including infants, children, adults and seniors.
- Footnote 1
The Codex Alimentarius Commission is an international organization under the auspices of the United Nations that develops international food standards, including MRLs.
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