Title: Parathion
CAS Registry Number: 56-38-2
CAS Name: Phosphorothioic acid O,O-diethyl O-(4-nitrophenyl) ester
Additional Names: O,O-diethyl O-p-nitrophenyl phosphorothioate; diethyl-p-nitrophenyl monothiophosphate; DNTP; S.N.P.
Manufacturers' Codes: E-605; AC-3422; ENT-15108
Trademarks: Alkron (Kerr-McGee); Folidol (Bayer); Fostox E (Siapa); Rhodiatox (Rhone-Poulenc); Thiophos
Molecular Formula: C10H14NO5PS
Molecular Weight: 291.26
Percent Composition: C 41.24%, H 4.84%, N 4.81%, O 27.47%, P 10.63%, S 11.01%
Literature References: Non-systemic contact and stomach insecticide and acaricide; cholinesterase inhibitor. Prepn: Thurston, FIAT Report 949 (1946); Coates, Topley, BIOS Final Report 1808 (1947). See also Fletcher et al., J. Am. Chem. Soc. 70, 3943 (1948). Conversion to toxic oxygen analogs: See Paraoxon. Toxicity study: T. B. Gaines, Toxicol. Appl. Pharmacol. 14, 515 (1969). Review: Hall in Adv. Chem. Ser. 1, entitled "Agricultural Control Chemicals" (ACS, Washington DC, 1950) p 150. Review of industrial syntheses: Chadwick, Watt, "Thiophosphates" in Phosphorus and Its Compounds vol. 2, J. R. Van Wazer, Ed. (Interscience, New York, 1961) pp 1257-1262. Review of distribution, transport and fate in the environment: M. S. Mulla et al., Residue Rev. 81, 1-159 (1981); of carcinogenic risk: IARC Monographs 30, 153-181 (1983).
Properties: Pale yellow liquid. bp760 375°; bp0.6 157-162°. mp 6°. nD25 1.5370. d425 1.26. Vapor pressure at 20°: 3.78´10-5 mm Hg. Surface tension at 25°: 39.2 dynes/cm. Viscosity (25°): 15.30 cP. Absorption spectra: Williams, Ind. Eng. Chem. 43, 950 (1951). Freely sol in alcohols, esters, ethers, ketones, aromatic hydrocarbons. Practically insol in water (20 ppm), petr ether, kerosene, and the usual spray oils. Incompatible with substances having a pH higher than 7.5. LD50 in female, male rats (mg/kg): 3.6, 13 orally; 6.8, 21 dermally (Gaines).
Melting point: mp 6°
Boiling point: bp760 375°; bp0.6 157-162°
Index of refraction: nD25 1.5370
Density: d425 1.26
Toxicity data: LD50 in female, male rats (mg/kg): 3.6, 13 orally; 6.8, 21 dermally (Gaines)
CAUTION: Potential symptoms of overexposure are miosis; rhinorrhea; headache; tight chest, wheezing, laryngeal spasm, salivation and cyanosis; anorexia, nausea, vomiting, abdominal cramps and diarrhea; sweating; muscle fasciculation, weakness and paralysis; giddiness, confusion and ataxia; convulsions, coma; low blood pressure; cardiac irregularities; skin, eye and respiratory system irritation. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 240; Clinical Toxicology of Commercial Products, R. E. Gosselin et al., Eds. (Williams & Wilkins, Baltimore, 5th ed., 1984) Section III, pp 336-343.
Use: Insecticide; acaricide. |