Methomyl

滅多威

S-methyl N-(methylcarbamoyloxy)thioacetimidate

methyl N-[[(methylamino)carbonyl]oxy]ethanimidothioate

[16752-77-5]

C₅H₁₀N₂O₂S

Insecticides > Carbamate insecticides

Insecticide, acaricide

Pyridaphenthion+methomyl+fenvalerate
Methomyl+phoxim
Methomyl+methamidophos
Methomyl+fenvalerate+phoxim
Methomyl+fenvalerate
Malathion+methomyl+fenvalerate
Lambda-cyhalothrin+methomyl+phoxim
Lambda-cyhalothrin+methomyl
Imidacloprid+methomyl
Fenpropathrin+methomyl+phoxim
Endosulfan+methomyl
Beta-cypermethrin+methomyl+phoxim
Beta-cypermethrin+methomyl
Liquid, low volatility liquid, water-soluble powder. 
Premix Parters: endosulfan; parathion; phosalone;

Molecular weight:162.2; Physical form:Colourless crystals, with a slight sulfurous odour. Density:1.2946 (25 °C); Composition:Methomyl is a mixture of (Z)- and (E)- isomers, the former predominating. Melting point:78-79 °C; Vapour pressure:0.72 (25 °C); Henry constant:2.13 × 10-6 Pa m3 mol-1; Partition coefficient(n-octanol and water):logP = 0.093; Solubility:In water 57.9 g/l (25 °C). In methanol 1000, acetone 730, ethanol 420, isopropanol 220, toluene 30 (all in g/, 25 °C). Sparingly soluble in hydrocarbons.; Stability:Stable in water for 30 d ( 5 and 7); 50 c. 30 d ( 9). Stable up to 140 °C. Stable to sunlight when exposed for 120 d.;

Oral:Acute oral 50 for male rats 34, female rats 30 /. Percutaneous:Acute percutaneous 50 for male and female rabbits >2000 /kg. Mild eye irritant (rabbits). Not a skin irritant (guinea pigs). Inhalation:50 (4 h) for rats 0.3 /l air (aerosol). Phytotoxicity:Non-phytotoxic when used as recommended, except to some vari

Ecotoxicology: 
Algae:50 (72 h) 60 /l.Bees:Toxic to bees, contact 50 0.1 mg/bee, but not hazardous when the spray has dried.Birds:Acute oral 50 for mallard ducks 15.9, pheasants 15.4 /kg. Dietary 50 (8 d) for Pekin ducks 1890, bobwhite quail 3680 / diet.Daphnia:50 (48 h) 31.7 mg/l.Fish:50 (96 h) for rainbow trout 3.4, bluegill sunfish 0.9 /l.Worms:50 (14 d) 23 / dry soil. 

Environmental fate: 
Animals:In rats, methomyl was rapidly converted to methomyl methylol, oxime, sulfoxide and sulfoxide oxime; these unstable intermediates were converted to acetonitrile and CO₂, which were eliminated primarily via respiration and in the urine. MetabolisSoil:Rapidly degraded in soil. 50 in groundwater samples <0.2 d (J. H. Smelt, Pestic. Sci., 1983, 14, 173-181). oc 72.Plant:50 following leaf application c. 3-5 d. Rapidly degraded to CO₂ and acetonitrile, with incorporation into natural plant components (J. Harvey & R. W. Reiser, Agric. Food Chem., 1973, 21

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