Prothiofos

Prothiofos

丙硫磷

(RS)-(O-2,4-dichlorophenyl O-ethyl S-propyl phosphorodithioate)

O-(2,4-dichlorophenyl) O-ethyl S-propyl phosphorodithioate

34643-46-4

C₁₁H₁₅Cl₂O₂PS₂

Insecticides > Organophosphorus insecticides

Insecticide

Molecular weight:345.2; Physical form:Colourless liquid, with a weak characteristic odour. Density:1.31 (20 °C); Flash point:>110 °C; Vapour pressure:0.3 mPa (20 °C); 0.6 mPa (25 °C); Partition coefficient(n-octanol and water):logP = 5.67 (20 °C); Solubility:In water 0.07 mg/l (20 °C). In dichloromethane, isopropanol, toluene >200 g/l (20 °C).; Stability:Hydrolysis DT50 in buffer (22 °C) 120 d ( pH 4), 280 d ( pH 7), 12 d ( pH 9). Photodegradation DT50 13 h.

Oral:Acute oral LD₅₀ for male rats 1569, female rats 1390, mice c. 2200 mg/ kg. Percutaneous:Acute percutaneous LD₅₀ (24 h) for rats >5000 mg/kg. Not irritating to skin and eyes (rabbits). Skin sensitiser. Inhalation: LC₅₀ (4 h) for rats >2.7 mg/l air (aerosol). Phytotoxicity:Russetting is possible with Golden Delicious apples. ADI:0.019 mg/ kg b.w.

Ecotoxicology:
 Algae: E_rC₅₀ for Scenedesmus subspicatus 2.3 mg/l.Bees:Not hazardous to bees if used as recommended.Birds:Acute oral LD₅₀ for Japanese quail 100-200 mg/ kg.Daphnia: LC₅₀ (48 h) 0.014 mg/l.Fish: LC₅₀ (96 h) for golden orfe 4-8, rainbow trout 0.5-1 mg/l (500 g/l EC formulation). 

Environmental fate: 
Animals:In rats, prothiofos is rapidly absorbed and metabolised. At 72 h after administration, 98% of the dose was excreted. Metabolic routes include oxidation to prothiofos-oxon, hydrolysis to 2,4-dichlorophenol which is further conjugated, and cleavage of the pSoil:Prothiofos is very strongly adsorbed in soil. DT₅₀ under field conditions is 1-2 mo. In soil, dechlorination to 4-chloroprothiofos and oxidation to prothiofos-oxon occurs, as well as hydrolysis to 2,4-dichlorophenol which is finPlant:In plants, prothiofos is hydrolysed to 2,4-dichlorophenol which is further conjugated. Formation of prothiofos-oxon and cleavage of the propyl group also occurs. WATER SOLUBILITY: 0.07 mg/l at 20° C

Signal Word:CAUTION; Hazard Class:II(Moderately hazardous)