Revision to the standard for the active constituent fenoxaprop-p-ethyl

The Australian Pesticides and Veterinary Medicines Authority (APVMA) invites comment from 30 July 2013 to 27 August 2013 on proposed changes to the current standard for the active constituent fenoxaprop-P-ethyl. The purpose of the change is to update the standard in accordance with the FAO standard published in 2010.

1. (Description) from:

• The material shall consist of fenoxaprop-P-ethyl together with related manufacturing impurities and shall be a white solid, free from visible extraneous matter and added modifying agents.


• To:



• The material shall consist of fenoxaprop-P-ethyl together with related manufacturing impurities, in the form of a beige to brownish crystalline solid, free from visible extraneous matter and added modifying agents.

3. (Chemical Name) (IUPAC): from:

• ethyl (R)-2-[4-(6-chloro-2-benzoxazol-2-lyoxy)phenoxy]propionate

To:

• (R)-2-[4-(6-chlorobenzoxazol-2-yloxy)phenoxy]propionic acid ethyl ester

6.1 (Composition) from:

• Active constituent: 880 g/kg minimum


• To:



• Active constituent: 920 g/kg minimum

See a copy of the new proposed standard for fenoxaprop-p-ethyl

For more information, see page 22 of the APVMA Gazette No. 15 – 30 July 2013.

Please send your comments by email to chemistry@apvma.gov.au or by mail to:

Manager, Pesticides Chemistry Evaluation Section
Australian Pesticides and Veterinary Medicines Authority
PO Box 6182
KINGSTON ACT 2609

Enquiries:

Telephone: +61 2 6210 4936
Fax: +61 2 6210 4840
Email: chemistry@apvma.gov.au

Draft standard for fenoxaprop-p-ethyl active constituent

Version 2 (draft)

1. Description: the material shall consist of fenoxaprop-P-ethyl together with related manufacturing impurities and shall be in the form of beige to brownish crystalline solid, free from visible extraneous matter and added modifying agents.

2. Common Name: fenoxaprop-P-ethyl

3. Chemical Name (IUPAC): (R)-2-[4-(6-chlorobenzoxazol-2-yloxy)phenoxy]propionic acid ethyl ester

4. CAS Number: 71283-80-2

5. Identity test: identity of the active constituent must be established by one or more of the following methods: spectroscopic tests (IR spectrum, NMR, mass spectra), Chromatography (HPLC or GC retention time with reference compound) or any other suitable test method.

6. Composition
6.1 Active constituent: 920 g/kg minimum

7. Analytical methods

• The analytical method used for the determination of the active constituent and toxicological significant impurities must be validated in accordance with the APVMA guidelines for the validation of analytical methods.
• The APVMA guidelines on validation of analytical methods state that "Analytical methods described in CIPAC handbooks and AOAC International Manual, and in recognized pharmacopoeias [BP, BP (Vet), Ph Eur and USP] for a particular active constituent or formulation are regarded as validated and do not require revalidation. However, the suitability of these methods must be verified under actual conditions of use i.e., the selectivity and accuracy of the method should be demonstrated for the published method when applied to the relevant sample matrix and laboratory conditions.
• When a CIPAC or AOAC method is used for the assay of an active constituent in a bulk active constituent, there is no matrix. The registrants need to check the specificity of the method to ensure there is no interference from impurities or degradation products. However, determination of accuracy of the method is not required as there is no matrix effect. However, when a CIPAC or AOAC method is used for the assay of an active constituent in a formulated product, determination of both specificity and accuracy is required as the matrix is relevant in formulated products (formulated products have different composition and quantities of excipients).
• Refer to Guidelines for the Validation of Analytical Methods for Active Constituent, Agricultural And Veterinary Chemical Products.
• Unless the scope of the collaborative method (CIPAC and AOAC) also includes toxicological significant impurities in the active constituent, validation data for impurities are required.

AOAC: Association of Official Analytical Chemists (The Official Methods of Analysis)
CIPAC: Collaborative International Pesticides Analytical Council