Specification :

Tefluthrin

Common name: tefluthrin; té fluthrine
IUPAC name: 2, 3, 5, 6-tetrafluoro-4-methylbenzyl ( Z) -( 1RS, 3RS) -3-( 2-chloro-3, 3, 3-trifluoroprop-1-enyl) -2, 2-dimethylcyclopropa necarboxylate
Roth: 2, 3, 5, 6-tetrafluoro-4-methylbenzyl ( Z) -( 1RS) -cis-3-( 2-chloro-3, 3, 3-trifluoroprop-1-enyl) -2, 2-dimethylcyclopropa necarboxylate
Chemical Abstracts name: [ 1a, 3a( Z) ] -( 2, 3, 5, 6-tetrafluoro-4-methylphenyl) methyl 3-( 2-chloro-3, 3, 3-trifluoro-1-propenyl) -2, 2-dimethylcyclopropanecarboxylate
CAS RN: [ 79538-32-2]

PHYSICAL CHEMISTRY
Composition: Tech. material is c. 92% pure. Mol. wt.: 418.7; M.f.: C17H14ClF7O2; Form: Colourless solid; ( tech., off-white) . M.p.: 44.6 º C; ( tech., 39-43 º C) . B.p.: 156 º C/ 1 mmHg. V.p.: 8.4 mPa ( 20 º C) ; 50 mPa ( 40 º C) . KOW: logP = 6.4 ( 20 º C) ; Henry: 2x102 Pa m3 mol-1 ( calc.) S.g./ density: 1.48 g/ ml ( 25 º C) . Solubility: In water 0.02 mg/ l ( purified and buffered, pH 5 and 9, 20 º C) . In acetone, hexane, toluene, dichloromethane, ethyl acetate > 500, methanol 263 ( all in g/ l, 21 º C) . Stability: Stable for at least 9 months at 15-25 º C. Stable for > 84 days at 50 º C. Stable to hydrolysis at pH 5-7 for > 30 days. At pH 9, 7% hydrolysis in 30 days. At pH 7, 27-30% loss in aqueous solution exposed to sunlight for 31 days. pKa: > 9 ( hydrolysis prevents measurement) . F.p.: 124 º C.

APPLICATIONS
Uses: Control of a wide range of soil insect pests, particularly those of the orders Coleoptera, Lepidoptera, and Diptera, in maize, sugar beet, wheat and other crops.
Formulation types: CS; EC; GR.

MAMMALIAN TOXICOLOGY
Oral: Oral and percutaneous LD50 values of tefluthrin depend on such factors as carrier, the test species, its sex, age and degree of fasting; values reported sometimes differ markedly. Acute oral LD50 for male rats 22, female rats 35 ( corn oil carrier) , male mice 46, female mice 57 mg/ kg.
Skin and eye: Acute percutaneous LD50 for male rats 316, female rats 177 mg/ kg. Slight eye and skin irritation ( rabbits) . No skin sensitisation ( guinea pigs) .
Inhalation: LC50 ( 4 h) for male rats 0.05, female rats 0.04 mg/ l.
NOEL: ( 2 y) for rats 25 mg/ kg diet; ( 1 y) for dogs 0.5 mg/ kg daily.
ADI: 0.005 mg/ kg.
Toxicity class: WHO ( a.i.) Ib
EC hazard: ( T+ R26/ 28 | R24 | N; R50)

ECOTOXICOLOGY
Birds: Acute oral LD50 for mallard ducks 4190, bobwhite quail 730 mg/ kg. Sub-acute dietary LC50 ( 5 d) for mallard ducks 2317, bobwhite quail 15 000 mg/ kg.
Fish: LC50 ( 96 h) for rainbow trout 60, bluegill sunfish 130 ng/ l. Under field conditions, adsorption of tefluthrin on bottom and suspended sediments should prevent any hazard.
Daphnia: EC50 ( 48 h) 70 ng/ l.
Algae: > 1.05 mg/ l.
Bees: LD50 ( contact) 280 ng/ bee; ( oral) 1880 ng/ bee.
Worms: 0.32 mg/ kg soil.

ENVIRONMENTAL FATE
Plants: No residues have been found on major crops treated at recommended rates ( limit of detection 0.01 mg/ kg) .
Soil/ Environment: DT50 in soil 150 d ( 5 º C) , 24 d ( 20 º C) , 17 d ( 30 º C) , partly due to loss by volatilisation. At normal application rates, there was no effect on soil microflora or earthworms.