NovaChem > Industry News > 2020 > Agricultural chemicals: 1-day withholding period

Agricultural chemicals: 1-day withholding period


Published on 13/10/2020


1. Position statement

The position of New Zealand Food Safety’s (NZFS) Agricultural Compounds and Veterinary Medicines (ACVM) team is that the withholding period (WHP) stated on the labels of registered products should reflect Good Agricultural Practice (GAP) first and foremost. For most agricultural chemicals used up until harvest, application on the day of harvest would appear to have little efficacious benefit. Consequently, it is ACVM’s position that a 1-day withholding period (WHP) is generally the minimum to be accepted as GAP, rather than the traditional nil WHP.

The ACVM team recognises that there are some situations where a nil WHP could still be acceptable, on a case-by-case basis. For example, where the data submitted has demonstrated that there would be a specific benefit from use right up until harvest, such as conferring post-harvest control. There may also be a perception that allowing application on the same day as harvest of the crop will give growers more flexibility. However, ACVM considers that this is an exception rather than GAP and may lead to excessive use and failure in achieving plant protection.

The change from a nil to a 1-day WHP for existing products does not affect how the residue profile has been assessed. It is not proposed to require more residue data for existing products affected by this change. However, where it is proposed that the existing ‘nil’ is changed to a longer WHP to reflect GAP, the changed residue profile will need to be addressed.

2. Action required by agrichemical and registrants

Product labels with an existing nil WHP must be updated when either a variation application or registration renewal application is made, by July 2022. This can be done in the following ways:
• Existing products with a nil WHP should be changed to 1-day, with no supporting information required.
• If the applicant wishes to retain a nil WHP for any use, this must be justified in terms of the use pattern to ensure it is GAP (note: efficacy data might be required to confirm a benefit from use right up until harvest, unless this was addressed in the original submission).
• If the applicant wishes to change a nil WHP to a longer WHP to reflect GAP, this use pattern must be justified. As well as efficacy, residues should also be addressed.

As per normal expectations for new registrations, residues and efficacy profiles relative to the use pattern proposed need to be addressed, including confirmation of a benefit from application immediately before harvest if this is proposed. Cross-reference to a nil WHP will be questioned if the referenced WHP has not been justified (note: some information supporting an amended WHP may have data protection).

ACVM is currently looking at amending our guidance to further clarify that WHPs should be based on GAP for all products, in line with this position statement. It is appreciated there will be a period when there is a mixture of labels in the market with nil or 1-day WHPs in the interim.

Note: Novachem will progressively modify our online listings, changing WHP's from nil to 1 day where applicable.




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