Thiometon

Thiometon

甲基乙拌磷

S-2-ethylthioethyl O,O-dimethyl phosphorodithioate

S-[2-(ethylthio)ethyl] O,O-dimethyl phosphorodithioate

640-15-3

C₆H₁₅O₂PS₃

Insecticides > Organophosphorus insecticides
Acaricides / Miticides > Organophosphorus acaricides

Insecticide, acaricide

Emulsifiable concentrate, ULV. Premix Parters: benomyl; carbendazim; carbendazim cymoxanil oxadixyl; carboxin; carboxin clothianidin metalaxyl; carboxin metalaxyl; imidacloprid; iprodione; isofenphos; metalaxyl thiabendazole; prochloraz; tebuconazole; thiophanate-methyl; tolclofos-methyl; triadimenol; vinclozolin;

Molecular weight:246.3; Physical form:Colourless liquid, with characteristic odour of sulfur-containing organophosphate esters.Boiling point 110°C at 0.1 mm Hg. At 20°C: Vapor pressure 23 mPa, specific gravity 1.209. Density:1.209 (20 °C); Vapour pressure:39.9 mPa (20 °C); Henry constant:2.840 × 10-2 Pa m3 mol-1 ( calc.); Partition coefficient(n-octanol and water):logP = 3.15 (mean, 20 °C); Solubility:In water 200 mg/l (25 °C). Readily soluble in common organic solvents. Slightly soluble in petroleum ether and mineral oils.; Stability:Good stability when in non-polar solvents, more unstable in the pure state. Easily hydrolyzed in aqueous solution at 25°C, 50% loss in 25 days at pH 3, 27 days at pH 6, 17 days at pH 9.

Oral:Acute oral LD₅₀ for male rats 73, female rats 136 mg/kg. Percutaneous:Acute percutaneous LD₅₀ for male rats 1429, female rats 1997 mg/kg. Not a skin irritant. Inhalation: LC₅₀ (4 h) in rats 1.93 mg/l air (actual value for 'Ekatin 50ZP'). Phytotoxicity:Non-phytotoxic, except for some ornamentals.

Ecotoxicology: 
Algae:EC₅₀ (96 h) for green algae 12.8 mg/l.Bees:Toxic to bees; LD₅₀ (oral) 0.56 µg/bee.Birds:Acute oral LD₅₀ (14 d) for male mallard ducks 95, female mallard ducks 53 mg/kg. Acute LD₅₀ (14 d) for male Japanese quail 46, female Japanese quail 60 mg/Daphnia: LC₅₀ (24 h) 8.2 mg/l.Fish:LC₅₀ (96 h) for carp 13.2, rainbow trout 8.0 mg/l (both under static conditions).Worms: LC₅₀ (7 d) 43.94 mg/kg soil; (14 d) 19.92 mg/kg soil. 

Environmental fate: 
Animals:Metabolism in animals is the same as in soil. Metabolism in rats showed that thiometon is rapidly and almost completely metabolised and excreted, mainly via urine. Metabolism proceeds via the conversion of P=S to P=O, oxidation of the sulfide to sulfoxideSoil:In soil, thiometon is metabolised to thiometon sulfoxide and thiometon sulfone. Thiometon: K_oc 579 ml/g (low mobility), DT₅₀ <1 d; thiometon sulfone: K_oc 52 ml/g (highly moPlant:Oxidation and hydrolytic reactions are the most important factors in degradation. The main metabolites are thiometon sulfoxide and thiometon sulfone. The corresponding P=O analogues occur only in very small quantities.

Hazard Class:Ib(Highly hazardous)