Title: Methyl Parathion
CAS Registry Number: 298-00-0
CAS Name: Phosphorothioic acid O,O-dimethyl O-(4-nitrophenyl) ester
Additional Names: O,O-dimethyl O-p-nitrophenyl phosphorothioate; O,O-dimethyl O-p-nitrophenyl thiophosphate; dimethyl parathion; parathion-methyl; metaphos
Manufacturers' Codes: E-601; ENT-17292
Trademarks: Folidol-M (Bayer CropSci.); Metacide (Bayer CropSci.); Penncap M (Cerexagri)
Molecular Formula: C8H10NO5PS
Molecular Weight: 263.21
Percent Composition: C 36.51%, H 3.83%, N 5.32%, O 30.39%, P 11.77%, S 12.18%
Literature References: Cholinesterase inhibitor. Prepn: Fletcher et al., J. Am. Chem. Soc. 72, 2461 (1950). Manuf: Faith, Keyes & Clark's Industrial Chemicals, F. A. Lowenheim, M. K. Moran, Eds. (Wiley-Interscience, New York, 4th ed., 1975) pp 552-555. Toxicity data: T. B. Gaines, Toxicol. Appl. Pharmacol. 14, 515 (1969). Review of carcinogenic risk: IARC Monographs 30, 131-152 (1983); of toxicology and human exposure: Toxicological Profile for Methyl Parathion (PB2001-109105, 2001) 267 pp.
Properties: Crystals from cold methanol, mp 37-38°. nD25 1.5367. d420 1.358. Soly in water 50 ppm; sol in most organic solvents. LD50 in male, female rats (mg/kg): 14, 24 orally; 67, 67 dermally (Gaines).
Melting point: mp 37-38°
Index of refraction: nD25 1.5367
Density: d420 1.358
Toxicity data: LD50 in male, female rats (mg/kg): 14, 24 orally; 67, 67 dermally (Gaines)
CAUTION: Potential symptoms of overexposure are irritation of eyes and skin; 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 214.
Use: Insecticide. |