Specification :

Es-fenvalerate

Common name: esfenvalerate
IUPAC name: ( S) -a-cyano-3-phenoxybenzyl ( S) -2-( 4-chlorophenyl) -3-methylbutyrate
Chemical Abstracts name: [ S-( R* , R* ) ] -cyano( 3-phenoxyphenyl) methyl 4-chloro-2-( 1-methylethyl) benzeneacetate
Other names: fenvalerate-U
CAS RN: [ 66230-04-4]

PHYSICAL CHEMISTRY
Composition: Tech. is 95% total isomers and 75% resolved ( S, S) - isomers. Mol. wt.: 419.9; M.f.: C25H22ClNO3; Form: Colourless crystals; ( tech., yellow-brown viscous liquid or solid at 23 º C) . M.p.: 59.0-60.2 º C; ( tech., 43.3-54 ° C) . B.p.: 151-167 º C ( tech.) V.p.: 2x 10-4 mPa ( 25 º C) . KOW: logP = 6.22 ( 25 º C) . Henry: 4.20x10-2 Pa m3 mol-1 ( calc.) S.g./ density: 1.26 ( 4-26 º C) Solubility: In water 0.002 mg/ l ( 25 º C) . In xylene, acetone, chloroform, ethyl acetate, dimethylformamide, dimethyl sulfoxide > 600, hexane 10-50, methanol 70-100 ( all in g/ kg, 25 º C) . Stability: Relatively stable to heat and light. Stable to hydrolysis at pH 5, 7 and 9 ( 25 ° C) . Specific rotation: [ a] D25 -15.0? ( c 2.0 in methanol) . F.p.: 256 ° C ( Pensky-Martens) .

APPLICATIONS
Biochemistry: Voltage dependent sodium channel agonist.
Mode of action: Insecticide with contact and stomach action.
Uses: A potent contact and ingested insecticide with a very broad range of activity, especially effective against Coleoptera, Diptera, Hemiptera, Lepidoptera and Orthoptera on cotton, fruit, vegetables and other crops, at 5-25 g a.i./ ha. It is effective against strains resistant to organochlorine, organophosphorus and carbamate insecticides.
Phytotoxicity: Some injury has been noted on crucifers, cucumbers, aubergines, tomatoes, pears and mandarin oranges.
Formulation types EC; SC; UL.

MAMMALIAN TOXICOLOGY
Oral: Acute oral LD50 for rats 75-88 mg/ kg.
Skin and eye: Acute percutaneous LD50 for rats > 5000, rabbits > 2000 mg/ kg. Slight skin irritant; mild eye irritant. Not a skin sensitiser.
NOEL: No effect on sub-chronic studies at 2 mg/ kg daily.
ADI: 0.02 mg/ kg.
Other: Acute LD50 values vary with the vehicle, concentration, route and species, etc.; values reported sometimes differ markedly. No carcinogenic, developmental or reproductive toxicity in animal tests.
Toxicity class: WHO ( a.i.) II; EPA ( formulation) II
EC hazard: T; R23/ 25| R43| N; R50, R53

ECOTOXICOLOGY
Birds: Acute oral LD50 for bobwhite quail 381 mg/ kg. LC50 ( 8 d) for bobwhite quail > 5620, mallard ducks 5247 ppm.
Fish: Extremely toxic to aquatic animals. LC50 ( 96 h) for fathead minnows 0.690, bluegill sunfish 0.26, rainbow trout 0.26 ug/ l.
Daphnia: LC50 ( 48 h) 0.24 ug/ l.
Bees: LD50 ( contact) 0.017 ug/ bee.

ENVIRONMENTAL FATE
Animals: Rapid metabolism and elimination occurs in rats and other animals. Primary metabolism involves hydroxylation of 2' - and 4' - hydroxyl moieties, ester cleavage, hydroxylation and oxidation of the alcohol derivatives, oxidation of the cyano moiety and conjugation of the acidic metabolites with sulfate, glycine and glucuronic acid.
Plants: The major metabolite was decarboxylated fenvalerate. Ester cleavage, hydration of the cyano group to carboxamide and carboxylic acid, hydroxylation of the 2' - and 4' - phenoxy positions, conversion of the alcohol moiety to 3-phenoxybenzyl alcohol and 3-phenoxybenzoic acid, and conjugation of the resulting carboxylic acids and alcohols with sugars, also occur.
Soil/ Environment: In sand ( 0.38% o.m.) , Kd ( 25 º C) 4.4; in sandy loam ( pH 7.3, 1.1% o.m.) , Kd ( 25 º C) 6.4, DT50 88 d; in silty loam ( pH 5.3, 2.0% o.m.) , Kd ( 25 º C) 71, DT50 114 d; in clay loam ( pH 5.7, 0.2% o.m.) , DT50 287 d; in clay loam ( pH 6.4, 1.5% o.m.) , Kd ( 25 º C) 105. Koc 5300.