Standards for indoxacarb

Indoxacarb is an insecticide that was first approved and registered in Australia in the early 2000s. Indoxacarb exists in two enantiomeric forms, with an optically active (asymmetric) carbon atom at the bridgehead of the oxadiazine ring. Only the S-enantiomer has insecticidal activity, with the R-enantiomer being inactive. The ISO common name ‘indoxacarb’ refers specifically to the active S-enantiomer, methyl (4aS)-7-chloro-2-{(methoxycarbonyl)[4-(trifluoromethoxy)phenyl]carbamoyl}-2,5-dihydroindeno[1,2-e][1,3,4]oxadiazine-4a(3H)-carboxylate.

The enantiomeric composition of commercially available indoxacarb active constituent has evolved over time with improvements in the manufacturing process allowing enantioselective synthesis. Originally, a technical material containing equal concentrations of the S- and R-enantiomers was developed. Later developments in the manufacturing process allowed the product of S-enantiomer enriched indoxacarb, including material with a 3:1 S/R enantiomer ratio, and later still, material with ≥ 9:1 S/R. Currently, technical active constituent with a minimum purity (i.e. S-enantiomer content) of 900 g/kg, and a manufacturing concentrate (technical concentrate), with a minimum of 467 g/kg, are commercially available.

The current APVMA active constituent standard covers only the manufacturing concentrate. It is therefore proposed to add a standard for indoxacarb technical active with a minimum purity of 900 g/kg, and to make minor amendments to the existing manufacturing concentrate standard (for example, updating the IUPAC name to the preferred IUPAC name).  These changes will bring the APVMA Standards into line with the FAO specification for indoxacarb, which includes separate specifications for indoxacarb technical active and indoxacarb manufacturing concentrate. 

The proposed new standard for indoxacarb technical active is available here.

The proposed amended standard for indoxacarb manufacturing concentrate is available here.

Comments on the proposal are invited from interested parties. The closing date for comments is 8 August 2019. Comments should be made in writing by post or email to:

Director Chemistry and Manufacture
Risk Assessment Capability Unit
Australian Pesticides and Veterinary Medicines Authority
PO Box 6182
KINGSTON ACT 2604
Phone: (02) 6770 2300
Email: enquiries@apvma.gov.au