Revision to the standard for the active constituent dimethoate

The Australian Pesticides and Veterinary Medicines Authority invites comment from 26 October 2016 to 27 January  2017 on proposed changes to the current standard for the active constituent dimethoate. The purpose of the change is to update the standard in accordance with advice arising from the reconsideration of dimethoate which is consistent with the FAO standard published in 2005.

1. (Description) from:

• the material shall consist of dimethoate together with related manufacturing impurities and shall be in the form of white to greyish crystals, free from visible extraneous matter and added modifying agents

To:

• The material shall consist of dimethoate together with related manufacturing impurities and shall be a white solid, having a mercaptanic odour, free from visible extraneous matter and added modifying agents.

6. Composition

6.1 Active constituent: 950 g/kg minimum—no change

6.2 Toxicological or relevant impurities:

0,0,S-trimethyl phosphorodithioate: 5 g/kg max—no change

ADD Omethoate CAS No. 1113-02-6: 2 g/kg max

ADD Isodimethoate CAS No. 3344-11-4: 3 g/kg max

ADD Water: 2 g/kg max

See below the new proposed standard for dimethoate.

Please send your comments by email to or by mail to:

Director, Chemical Review
Australian Pesticides and Veterinary Medicines Authority
PO Box 6182
KINGSTON ACT 2609

Telephone: +61 2 6210 4947
Fax: +61 2 6210 4776
Email: chemicalreview@apvma.gov.au

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Draft standard for dimethoate active constituent

Version 2 (draft)

Effective date: TBA

1. Description: The material shall consist of dimethoate together with related manufacturing impurities and shall be a white solid, having a mercaptanic odour, free from visible extraneous matter and added modifying agents.

2. Common Name: Dimethoate.

3. Chemical Name (IUPAC): O,O-dimethyl S-methylcarbamoylmethyl phosphorodithioate

4. CAS Number: 60-51-5.

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: 950 g/kg minimum

6.2 Toxicological or relevant impurities:

0,0,S-trimethyl phosphorodithioate: 5g/kg max

Omethoate  CAS No. 1113-02-6: 2 g/kg max

Isodimethoate CAS No. 3344-11-4: 3 g/kg max

Water: 2 g/kg max

7. Analytical methods

¹Collaborative International Pesticides Analytical Council
²Association of Official Analytical Chemists (The Official Methods of Analysis)