Title: Fenthion
CAS Registry Number: 55-38-9
CAS Name: Phosphorothioic acid O,O-dimethyl O-[3-methyl-4-(methylthio)phenyl] ester
Additional Names: O,O-dimethyl O-(4-methylmercapto-3-methylphenyl) thionophosphate; O,O-dimethyl O-(3-methyl-4-methylthiophenyl) thiophosphate; O,O-dimethyl O-(4-methylthio-3-methylphenyl) thiophosphate; O,O-dimethyl O-[4-(methylthio)-m-tolyl] phosphorothioate; 4-methylmercapto-3-methylphenyl dimethyl thiophosphate
Manufacturers' Codes: Bayer 29493; ENT-25540; S-1752
Trademarks: Baycid (Bayer); Baytex (Parke-Davis); Entex (obsolete); Lebaycid; Mercaptophos (Bayer); Queletox; Talodex; Tiguvon (Bayer)
Molecular Formula: C10H15O3PS2
Molecular Weight: 278.33
Percent Composition: C 43.15%, H 5.43%, O 17.25%, P 11.13%, S 23.04%
Literature References: Cholinesterase inhibitor. Prepn: Schrader, Die Entwicklung neuer insektizider Phosphorsäure-Ester (Verlag Chemie, 3rd ed., 1963) pp 298-313; Schlegk, Schrader, DE 1116656 C.A. 56, 14170g (1962); and US 3042703 (1961 and 1962, both to Bayer); Nishizawa, Mizutani, JP 64 15130 (1964 to Sumitomo), C.A. 61, 16016h (1964). Properties: Jung, Bull. WHO 21, 215 (1959); Schrader, loc. cit. Toxicity: Gaines, Toxicol. Appl. Pharmacol. 2, 88 (1960).
Properties: Liquid, slight odor of garlic. bp0.01 87°. Commercial product, bp0.01 105°. d420 1.250. nD20 1.5698. Vapor pressure at 20°: 3´10-5 mm Hg. Thermally stable up to 210°; resistant to alkalies up to pH 9. Readily sol in methanol, ethanol, ether, acetone and many other organic solvents, esp chlorinated hydrocarbons. Practically insol in water (55 mg/l). LD50 in male, female rats (mg/kg): 215, 245 orally (Gaines).
Boiling point: bp0.01 87°; bp0.01 105°
Index of refraction: nD20 1.5698
Density: d420 1.250
Toxicity data: LD50 in male, female rats (mg/kg): 215, 245 orally (Gaines)
CAUTION: Potential symptoms of overexposure are nausea, vomiting, abdominal cramps, diarrhea, salivation; headache, giddiness, vertigo, weakness; rhinorrhea, chest tightness; blurred vision, miosis; cardiac irregularities; muscle fasciculations; dyspnea. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 144.
Use: Insecticide; acaricide.
Therap-Cat-Vet: Ectoparasiticide. |