Fenamiphos

Fenamiphos

苯线磷

(RS)-(ethyl 4-methylthio-m-tolyl isopropylphosphoramidate)

ethyl 3-methyl-4-(methylthio)phenyl (1-methylethyl)phosphoramidate

22224-92-6

C₁₃H₂₂NO₃PS

Nematicides > Organophosphorus nematicides
Insecticides > Organophosphorus insecticides

Nematicide

Emulsifiable concentrate, granule, oil-in-water emulsion. 
Premix Parters: captan;

Molecular weight:303.4; Physical form:Colourless crystals; ( tech., tan, waxy solid). Density:1.191 (23 °C); Melting point:49.2 °C; ( tech., 46 °C); Flash point:c. 200 °C; Vapour pressure:0.12 mPa (20 °C); 4.8 mPa (50 °C); Henry constant:9.1 × 10-5 Pa m3 mol-1 (20 °C); Partition coefficient(n-octanol and water):logP = 3.30 (20 °C); Solubility:In water 0.4 g/l (20 °C). In dichloromethane, isopropanol, toluene >200, hexane 10-20 (all in g/l, 20 °C).; Stability:Hydrolysis DT50 1 y ( pH 4), 8 y ( pH 7), 3 y ( pH< 9) (22 °C).;

Oral:Acute oral LD₅₀ for male and female rats c. 6, mice, dogs and cats c. 10 mg/ kg. Percutaneous:Acute percutaneous LD₅₀ for rats c. 80 mg/kg. Slightly irritant to skin and eyes (rabbits). Inhalation: LC₅₀ (4 h) for rats c. 0.12 mg/l air (aerosol). Phytotoxicity:Non-phytotoxic when applied to the soil.

Ecotoxicology: 
Algae: E_rC₅₀ for Scenedesmus subspicatus 11 mg/l.Birds:Acute oral LD₅₀ for bobwhite quail 0.7-1.6, mallard ducks 0.9-1.2 mg/kg. Dietary LC₅₀ (5 d) for mallard ducks 316, bobwhite quail 38 mg/ kg diet.Daphnia: LC₅₀ (48 h) 0.0019 mg/l.Fish: LC₅₀ (96 h) for bluegill sunfish 0.0096, rainbow trout 0.0721 mg/l.Worms: LC₅₀ for Eisenia foetida 795 mg/ kg dry soil (400 EC). 

Environmental fate: 
Animals:In mammals, following oral administration, there is rapid metabolism involving oxidation to the sulfoxide and sulfone analogues, followed by subsequent hydrolysis, conjugation and excretion via the urine; some N-dealkylation also occurs (T. B. WaSoil:No effect on soil bacteria. Readily degradable in water, degradable on soil surfaces. Duration of activity in soil is c. 4 months. Based on K_oc values and leaching studies, fenamiphos can be classified as a compound wiPlant:Degradation is by thiooxidation and hydrolysis. The major metabolites are fenamiphos sulfoxide and fenamiphos sulfone ( idem, ibid.).

Hazard Class:Ia(Extremely hazardous)