Proposed Maximum Residue Limit PMRL2013-18, Flumioxazin

Pest Management Regulatory Agency
17 April 2013
ISSN: 1925-0843 (PDF version)
Catalogue number: H113-24/2013-18E-PDF (PDF version)

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Under the authority of the  Pest Control Products Act, Health Canada's Pest Management Regulatory Agency (PMRA) has concluded that the addition of new uses on Tree Nuts (Crop Group 14-11) to the product label of Chateau® Herbicide WDG, containing technical grade flumioxazin, is acceptable. The specific uses approved in Canada are detailed on the label of Chateau® Herbicide WDG, Pest Control Products Act Registration Number 29231.

The evaluation of this flumioxazin application indicated that the end-use product has merit and value and the human health and environmental risks associated with the new uses 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.

Consultation on the proposed MRLs for flumioxazin is being conducted via this document (see Next Steps). A summary of the field trial data used to support the proposed MRLs can be found in Appendix I.

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  Standards Council of Canada.

The proposed MRLs, to be added to the MRLs already established for flumioxazin, are as follows.

Table 1 - Proposed Maximum Residue Limits for Flumioxazin

Common Name	Residue Definition	MRL (Table 1 footnote ppm)	Food Commodity
Footnotes Footnote 1 = parts per million Return to table 1 footnote ppm referrer
FFlumioxazin	2-[7-fluoro-3,4-dihydro-3-oxo-4-(2-propynyl)-2H-1,4-benzoxazin-6-yl]-4,5,6,7-tetrahydro-1H-isoindole-1,3(2H)-dione	0.02	Tree nuts (Crop Group 14-11), turnip tops

MRLs are proposed for each food commodity included in the Brassica subgroups in accordance with the Residue Chemistry Crop Groups webpage in the Pesticides and Pest Management section of Health Canada's website.

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 pesticides(s) or for food commodity(ies).

International Situation and Trade Implications

The MRLs proposed for flumioxazin 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 MRLs^{Footnote 1} listed for flumioxazin in or on any commodity on the Codex Alimentarius Pesticide Residues in Food webpage.

Next Steps

The PMRA invites the public to submit written comments on the proposed MRLs for flumioxazin 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.

Appendix I - Summary of Field Trial Data Used to Support the Proposed MRLs

Residue data from supervised residue trials conducted in the US were submitted to support the domestic use of Chateau® Herbicide WDG on Tree Nuts (Crop Group 14-11). Flumioxazin was applied to almonds and pecans at exaggerated rates, and harvested according to label directions.

Maximum Residue Limit(s)

The recommendation for maximum residue limits (MRLs) for flumioxazin was based upon the submitted field trial data, and guidance provided in the OECD MRL Calculator Statistical White Paper. Table A1 summarizes the data used to calculate the MRL for tree nuts.

Table A1 Summary of Field Trial and Processing Data Used to Support Maximum Residue Limit(s) (MRLs)

Commodity	Application Method/Total Application Rate (g a.i./ha)	PHI (days)	Residues (ppm)		Experimental Processing Factor
			Min	Max
Pecan nutmeats	Broadcast spray/ 841.7-851.8	42-61	<0.02	<0.02	Not applicable
Almond nutmeats	Broadcast spray/ 836.0-849.3	60-61	<0.01	<0.01

Following the review of all available data, an MRL of 0.02 ppm is recommended to cover residues on flumioxazin in/on Tree Nuts (Crop Group 14-11). Residues of flumioxazin in these tree nut commodities at the proposed MRL will not pose an unacceptable risk to any segment of the population, including infants, children, adults and seniors.