Omethoate

Omethoate

氧乐果

2-dimethoxyphosphinoylthio-N-methylacetamide
or
O,O-dimethyl S-methylcarbamoylmethyl phosphorothioate

O,O-dimethyl S-[2-(methylamino)-2-oxoethyl] phosphorothioate

1113-02-6

C₅H₁₂NO₄PS

Insecticides > Organophosphorus insecticides

Insecticide, acaricide

Triadimefon+omethoate
Imidacloprid+omethoate
Fenvalerate+omethoate
Fenpropathrin+omethoate
Dichlorvos+fenvalerate+omethoate
Deltamethrin+omethoate
Beta-cypermethrin+omethoate

Molecular weight:213.2; Physical form:Colourless liquid, with a mercaptan odour. Density:1.32 (20℃); Melting point:Solidifies -28 ℃ (tech.); Flash point:128 ℃( tech.); Vapour pressure:3.3 mPa (20℃); Partition coefficient(n-octanol and water):logP = -0.74 (20℃); Solubility:Readily soluble in water, alcohols, acetone, and many hydrocarbons. Slightly soluble in diethyl ether. Almost insoluble in petroleum ether.; Stability:Hydrolysed in alkaline media; relatively slowly hydrolysed in acidic media: DT50 (est.) 102 d (pH 4), 17 d (pH 7), 28 h (pH 9) (22 ℃).

Oral:Acute oral LD₅₀ for rats c. 25 mg/ kg. Percutaneous:Acute percutaneous LD₅₀ (24 h) for male rats 232, female rats c. 145 mg/kg. Not irritating to the skin; slightly irritating to the eyes (rabbits). Inhalation: LC₅₀ (4 h) for rats c. 0.3 mg/l (aerosol). Phytotoxicity:May be phytotoxic to some varieties of peach.

Ecotoxicology: Algae: E_rC₅₀ for Scenedesmus subspicatus 167.5 mg/l.Bees:Toxic to bees.Birds:Acute oral LD₅₀ for male Japanese quail 79.7, female Japanese quail 83.4 mg/ kg.Daphnia: LC₅₀ (48 h) 0.022 mg/l.Fish: LC₅₀ (96 h) for golden orfe 30, rainbow trout 9.1 mg/l.Worms: LC₅₀ for Eisenia foetida 46 mg/ kg dry soil. Environmental fate: Animals:Omethoate is not accumulated in animal tissues or fat. The main metabolites in the urine are O-demethylomethoate and N-methyl-2-(methyldithio)acetamide.Soil:Omethoate has a relatively high mobility in soil but is very rapidly metabolised; 50 only a few days. The main metabolite is CO₂. Aged leaching studies revealed that metabolites have only a low leaching potential.Plant:Omethoate is rapidly taken up by plants. Demethylation and hydrolysis of P-S bonds are the main metabolic steps. The main metabolites are 3-hydroxy-3-[(2-methylamino-2-oxo-ethyl)thio]propionic acid and its oxidation products. WATER SOLUBILITY: Readily Soluble

Signal Word:DANGER; Hazard Class:Ib(Highly hazardous)