TRIAZOPHOS
IDENTIFICATION
Common name: Triazophos
Other name: triazophos (BSI, E ISO, (m) F-ISO)
Iupac name: O,O-diethyl O-1-phenyl-lH-1,2,4-triazol-3-yl phosphorothioate
Chemical abstracts name: O, 0-diethyl O-(1-phenyl-1H-1,2,4-triazol-3-yl) phosphorothioate
Type: Insecticide for Agriculture
CAS RN: [24017 47-8]
M.F.: C12H16N3O3PS
Mol Wt: 313.3
PHYSICAL CHEMISTRY
Form (appearance): Light yellow to dark brown liquid, with a typical phosphate ester odour .
Composition: Tech. grade is ≥92% pure.
M.P.: 0-5℃
B.P.: Exothermic decomposition above 140℃
V.P.: 0.39 mPa (30℃); 13 mPa (55℃)
F.P.: Cannot be determined; exothermic decomposition above 140℃
S.G.: 1.24 (20℃)
Solubility.: In water 39 mg/l (pH 7, 20℃). In acetone, dichloromethane, methanol, isopropanol, ethyl acetate and polyethyleneglycols >500, n-hexane 11.1 (all in g/l, 20℃).
Stability: Stable to light. Hydrolysed by aqueous acids and alkalis.
KowlogP: 3.34
APPLICATION
Formulation types: EC; UL.
Biochemistry: Cholinesterase inhibitor.
Mode of action: Broad-spectrum insecticide and acaricide with contact and stomach action. Non systemic, but penetrates deeply into plant tissues.
Uses: Control of aphids, thrips, midges, beetles, lepidopterous larvae, cutworms and other soil insects, spider mites and other species of mite, etc. in ornamentals, fruit trees (including citrus - 0.03%-0.1%), vines, bananas, strawberries, vegetables (200- 600 g/ha), oilseed rape, cereals, sugar beet, sugar cane, maize, soya beans, peanuts, guavas, mangoes, oil palms, olives, cotton (250-600 g/ha), coffee, rice (200-400 g/ha), grassland, and in forestry. Also controls some free living nematodes, particularly in ornamentals and strawberries, and as a bulb dip for tulips and garlic.
MAMMALIAN TOXICOLOGY
Oral: Acute oral LD50 for rats 57 59, dogs >320->500 mg/kg b.w. daily.
Skin and eye: Acute dermal LD50 for rats >2000 mg/kg. No skin or eye irritation.
Inhalation: LC50 (4 h) for rats 0.531 mg/l air.
Noel: In 2 y feeding trials, rats receiving 1 mg/kg diet and dogs receiving 0.3 mg/kg diet were unaffected, except for inhibition of blood serum cholinesterase.
ADI: (JMPR) 0.001 rog/kg b.w. [1993].
Toxicity: WHO (a.i.) lb EC hazard T; R23/251Xn; R211 N; RS0, R53
ECOTOXICOLOGY
Birds: Acute oral LDs0 for Japanese quail 4.2-27.1 rog/kg, depending on carrier and sex. LC50 (8 d) for mallard ducks 325 mg/kg diet.
Fish: LC50 (96 h) for carp 5.6, golden orfe 7.5 18 mg/I. LC50 (21 d) for trout 0.01 mg/l.
Daphnia: LC50 (48 h) 0.003 mg/l.
Algae: LC50 (96 h) 1.15 mg/l.
Worms: LC50 (14 d) for Eisenio foetida 187 mg/kg dry artificial soil. Bees Toxic to honeybees.
ENVIRONMENTAL FATE
Plant: EHC 63(WHO, 1986; a general review of organophosphorus insecticides).
In cotton plants, 1-phenyl-3-hydroxy-1,2,4-triazole is found as a metabolite, and the occurrence of a desethyl derivative of triazophos is presumed (W. G. Thier et al., Fresenius`Z. Anal. Chem., 1973, 267, 181 186).
Animals: Mainly eliminated via urine (75 94% of applied radioactivity). Excretion DT50 <1 d.
Soil/Environment: DT50 (aerobic, field) 6-12 d, DT50 39 114 d. DT50 (lab.) 7 46 d, DT50 109 181 d. Water: rapidly degraded in aquatic systems;DT50 (elimination from water) <3 d, (elimination from water/sediment system) <11 d; DT50 (elimination from the system) <47 d. |
