Parathion methyl

Parathion methyl
Names
IUPAC name
O,O-Dimethyl-O-p-nitrophenylphosphorothioate
Other names
Azophos, Methyl parathion, O,O-Dimethyl O-4-nitrophenyl phosphorothioate, O,O-Dimethyl-p-nitrophenylthionophosphate
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.005.501 Edit this at Wikidata
EC Number
  • 015-035-00-7
RTECS number
  • TG0175000
UNII
UN number 2783
  • InChI=1S/C8H10NO5PS/c1-12-15(16,13-2)14-8-5-3-7(4-6-8)9(10)11/h3-6H,1-2H3
    Key: RLBIQVVOMOPOHC-UHFFFAOYSA-N
  • InChI=1/C8H10NO5PS/c1-12-15(16,13-2)14-8-5-3-7(4-6-8)9(10)11/h3-6H,1-2H3
    Key: RLBIQVVOMOPOHC-UHFFFAOYAW
  • COP(=S)(OC)Oc1ccc(cc1)[N+](=O)[O-]
Properties
(CH3O)2P(S)OC6H4NO2
Molar mass 263.2 g/mol
Appearance White to tan, crystalline solid or powder[1]
Odor pungent, garlic-like[1]
Density 1.36 g/mL (20°C)[1]
Melting point 37 °C; 99 °F; 310 K[1]
Boiling point 143 °C; 289 °F; 416 K[1]
0.006% (25°C)[1]
Vapor pressure 0.00001 mmHg (20°C)[1]
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
 reactive with strong oxidizers and water[1]
Lethal dose or concentration (LD, LC):
67 mg/kg (rat, dermal)[2]
10-25 mg/kg (male rat, oral)[3]
24 mg/kg (female rat, oral)[3]
NIOSH (US health exposure limits):
PEL (Permissible)
 none[1]
REL (Recommended)
 TWA 0.2 mg/m3 [skin][1]
IDLH (Immediate danger)
 N.D.[1]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Parathion methyl, or methyl parathion, is an organophosphate insecticide, possessing an organothiophosphate group. It is structurally very similar to parathion-ethyl. It is not allowed for sale and import in nearly all countries around the world, while a few allow it under subject to specified conditions only.

  1. ^ a b c d e f g h i j k NIOSH Pocket Guide to Chemical Hazards. "#0427". National Institute for Occupational Safety and Health (NIOSH).
  2. ^ Cite error: The named reference SN was invoked but never defined (see the help page).
  3. ^ a b "Methyl Parathion". 1988 OSHA PEL Project Documentation. NIOSH. 28 September 2011.