Etofenprox

NOMENCLATURE
Common name: etofenprox; ethofenprox
IUPAC name: 2-(4-ethoxyphenyl)-2-methylpropyl 3-phenoxybenzyl ether
Chemical Abstracts name: 1-[[2-(4-ethoxyphenyl)-2-methylpropoxy]methyl]-3-phenoxybenzene
CAS RN: [80844-07-1]

PHYSICAL CHEMISTRY
Mol. wt.: 376.5; M.f.: C₂₅H₂₈O₃; Form: White crystals. M.p.: 36.4-38.0 ^oC; B.p.: 200

^oC/0.18 mmHg. V.p.: 32 mPa (100 ^oC). KOW: logP = 7.05 (25 ^oC). S.g./density: 1.157 (23 ^oC,

solid); 1.067 (40.1 ^oC, liquid). Solubility: In water <1 ug/l (25 ^oC). In chloroform 9,

acetone 7.8, ethyl acetate 6, xylene 4.8, methanol 0.066 (all in kg/l, 25 ^oC). Stability:

Stable in acidic and alkaline media at 80 ^oC for >90 days, and to light.

APPLICATIONS
Mode of action: Insecticide with contact and stomach action.
Uses: Control of rice water weevils, skippers, leaf beetles, leafhoppers, planthoppers, and

bugs on paddy rice; and aphids, moths, butterflies, whitefly, leaf miners, leaf rollers,

leafhoppers, thrips, borers, etc. on pome fruit, stone fruit, citrus fruit, tea, soya

beans, sugar beet, brassicas, cucumbers, aubergines, and other crops. Also used to control

public health pests, and on livestock.
Formulation types: CS; DP; EW; EC; GR; SL; UL; WP.

MAMMALIAN TOXICOLOGY
Oral: Acute oral LD50 for male and female rats >42 880, male mice >107 200, dogs >5000

mg/kg.
Skin and eye: Acute percutaneous LD₅₀ for rats and male and female mice >2140 mg/kg; non-

irritating to skin and eyes (rabbits).
Inhalation: LC₅₀ (4 h) for rats 5900 mg/m3.
NOEL: (1 y) for dogs 32 mg/kg diet; (2 y) for male rats 3.7, female rats 4.8, male mice

3.1, female mice 3.6 mg/kg diet. In life-span feeding studies on rats and mice, at doses up

to 4900 ppm, and on dogs, at doses up to 10 000 ppm, no adverse effects were observed.

Mutagenicity, teratogenicity, and three-generation reproduction studies showed no

noticeable abnormalities.
ADI: 0.03 mg/kg b.w.
Toxicity class: WHO (a.i.) III (Table 5); EPA (formulation) IV

ECOTOXICOLOGY
Birds: Acute oral LD₅₀ for mallard ducks >2000 mg/kg.
Fish: TLm (48 h) for carp 5.0 ppm.
Daphnia: LC₅₀ (3 h) >40 mg/l.
Worms: LC₅₀ for earthworms (7 d) 43.1 ppm, (14 d) 24.6 ppm.

ENVIRONMENTAL FATE
Animals: In rats, parent compound, 2-(4-hydroxyphenyl)-2-methylpropyl 3-(phenoxybenzyl)

ether, and 2-(4-ethoxyphenyl)-2-methylpropyl 3-(4-hydroxybenzyl) ether are found.
Plants: In rice, the main metabolite is 2-(4-ethoxyphenyl)-2-methylpropyl 3-

phenoxybenzoate.
Soil/Environment: DT₅₀ in soil c. 6 d.

?