Common name: Oxyfluorfen
Other name: oxyfluorfen (BSI, E-ISO, ANSI, WSSA); oxyfluorfene ((m) F-ISO)
Iupac name: 2-chloro-α,α,α-trifiuoro-p-tolyl-3-ethoxy-4-nitrophenyl ether Chemical Abstracts name 2-chloro-1-(3-ethoxy-4- nitrophenoxy)-4-(trifluoromethyl)benzene
Chemical abstracts name: [42874-03-3]
Mol Wt: 361.7
Form (appearance): Orange, crystalline solid.
M.P.: 85-90℃; (tech., 65-84℃)
B.P.: 358.2℃ (decomp.)
V.P.: (pure a.i.) 0.0267 mPa (7-5℃)
S.G.: 1.35 (73℃)
Solubility.: In water 0.116 mg/l (25℃). Readily soluble in most organic solvents, e.8. acetone 72.5, cyclohexanone, isophorone 61.5, dimethylformamide >50, chloroform 50-55, mesityl oxide 40-50 (all in g/100 g, 25℃).
Stability: No significant hydrolysis in 28 d at pH 5-9 (25℃). Decomposed rapidly by u.v. irradiation; UT50 3 d (room temperature). Stable up to 50℃.
Formulation types: EC; GR.
Biochemistry: Protoporphyrinogen oxidase inhibitor.
Mode of action: Selective contact herbicide, absorbed more readily by the foliage (and especially the shoots) than by the roots, with very little translocation.
Uses: Control of annual broad-leaved weeds and grasses in a variety of tropical and subtropical crops, by pre- or post-emergence application at rates in the range 0.25-2.0 kg a.i./ha. Particular crops include tree fruit (including citrus), vines, nuts, cereals, maize, soya beans, peanuts, rice, cotton, bananas, peppermint, onions, garlic, ornamental trees and shrubs, and conifer seedbeds.
Phytotoxicity: Soya beans and cotton may be injured by contact with oxyfiuorfen.
Oral: Acute oral LD50 for rats and dogs >5000 mg/kg.
Skin and eye: Acute percutaneous LD50 for rabbits >10000 mg/kg. Mild to moderate eye irritant; mild skin irritant (rabbits).
Inhalation: LC50 >5.4 mg/l.
Noel: In chronic dietary trials, NOEL for rats 40, dogs 100, mice 2 mg/kg diet.
ADI: 0.003 mg/kg.
Toxicity: WHO (a.i.) III (Table 5); EPA (formulation) IV
Birds: Acute LD50 for bobwhite quail >2150 mg/kg. Dietary LC50 (8 d) for mallard ducks and bobwhite quail >5000 ppm.
Fish: LC50 (96 h) for bluegill sunfish 0.2. trout 0.41, channel catfish 0.4 mg/l.
Daphnia: LC50 (48 h) 1.5 mg a.i./l.
Worms: Bees Not toxic to honeybees at 0.025 mg a.i./bee.
Plant: Not readily metabolised in plants.
Animals: For details of metabolism, see I. L. Adler et al., J. Agric. Food Chem., 1977, 25, 1339.
Soil/Environment: Strongly adsorbed on soil, not readily desorbed, and shows negligible leaching. Koc from 2891 (sand) to 32381 (silty clay loam). Photodecomposition in water is rapid, and on soil is slow. Microbial degradation is not a major factor. Field dissipation DT50 5-55 d; soil DT50 (in dark) (aerobic) 292 d, (anaerobic) c. 580 d.