Bromacil

Bromacil

除草定

(RS)-5-bromo-3-sec-butyl-6-methyluracil

5-bromo-6-methyl-3-(1-methylpropyl)-2,4(1H,3H)-pyrimidinedione

314-40-9

C₉H₁₃BrN₂O₂

Herbicides > Uracil herbicides

Herbicide

Granular, liquid, water soluble liquid, wettable powder. Premix Parters: tetradifon;

Molecular weight:261.1; Physical form:Colourless crystals. Density:1.59 (23 °C); Melting point:157.5-160 °C; Vapour pressure:4.1 × 10-2 mPa(25 °C); Partition coefficient(n-octanol and water):logP = 1.88 (pH 5); pKa:9.27, v. weak acid; Solubility:In water 807 ( pH 5), 700 ( pH 7), 1287 ( pH 9) (all in mg/l, 25 °C). In ethanol 134, acetone 167, acetonitrile 71, xylene 32, 3% aqueous sodium hydroxide 88 (all in g/l, 25 °C).; Stability:Thermally stable up to the melting point. Stable in aqueous bases. Slowly decomposed by concentrated acids.;

Oral:Acute oral LD₅₀ for male rats 2000, female rats 1300 mg/kg (for 80% formulation). Percutaneous:Acute percutaneous LD₅₀ for rabbits >5000 mg/kg. Mild eye and moderate skin irritant. Non-sensitising to skin. Inhalation:LC₅₀ (4 h) for rats >4.8 mg/l air.

WATER SOLUBILITY: 815 ppm at 25°C SOIL PARTICLE ADSORPTION: Bromacil can seep or leach through soil and can enter groundwater which may be used as drinking water. Procedures must be followed to minimize potential bromacil movement into groundwater HAZARDS: Fish: LC₅₀ 28 ppm (rainbow trout); 71 ppm (bluegill). 

Ecotoxicology: 
Bees:Not toxic to bees.Birds:Acute oralLD₅₀ for bobwhite quail 2250 mg/kg. DietaryLC₅₀ (8 d) for mallard ducks and bobwhite quail >10 000 mg/ kg diet.Daphnia: LC₅₀ (48 h) 119 mg/l.Fish: LC₅₀ (48 h) for rainbow trout 75, bluegill sunfish 71, carp 164 mg/l.Other aquatic spp.:LC₅₀ for mysid shrimp (Mysidopsis bahia) 112.9 mg/l; EC₅₀ for oyster embryo larvae 130 mg/l. 

Environmental fate: Animals:
The principal metabolite is 5-bromo-3-sec-butyl-6-hydroxymethyluracil (J. Agric. Food Chem., 1969, 17, 967-973).Soil:Duration of residual activity in soil is c. 5 .Plant:See animals.

Signal Word:CAUTION; Hazard Class:III(Slightly hazardous)