Methyl parathion

  • Phosphorothioic acid, O,O-dimethyl O-(4-nitrophenyl) ester
  • O,O-Dimethyl O-4-nitrophenyl phosphorothioate
  • Metron
  • Metaphos
  • p-Nitrophenylthionophosphate
  • Parathion-Methyl
Formula
C8H10NO5PS
Structure
Description
Methyl parathion is a white crystalline solid.
Uses
It controls aphids, boll weevils, & mites esp well, although its spectrum for control of insects is nearly as broad as parathion.

Registry Numbers and Inventories.
CAS
298-00-0
EC (EINECS/ELINCS)
206-050-1
EC Index Number
015-035-00-7
EC Class
Very toxic; Toxic
RTECS
TG0175000
RTECS class
Agricultural Chemical and Pesticide; Tumorigen; Mutagen; Reproductive Effector
UN (DOT)
2783
Merck
12,6183
Beilstein/Gmelin
1914724
RCRA
P071
EPA OPP
53501
Swiss Giftliste 1
G-2517
Austrailia AICS
Listed
New Zealand
Listed

Properties.
Formula
C8H10NO5PS
Formula mass
263.21
Melting point, °C
37 - 38
Boiling point, °C
335
Vapor pressure, mmHg
0.00024 (25 C)
Vapor density (air=1)
1.358
Odor Threshold Odor threshold 0.1328 mg/m3
Density
1.358 g/cm3 (20 C)
Solubility in water
55 mg/L
Refractive index
1.5367 (20 C)
Partition coefficient, pKow
2.86
Heat of vaporization
55.5 kJ/mol

Hazards and Protection.
Storage
Keep in a cool, dry, dark location in a tightly sealed container or cylinder. Keep away from incompatible materials, ignition sources and untrained individuals. Secure and label area. Protect containers/cylinders from physical damage.
Handling
All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Protection
Wear appropriate protective gloves, clothing and goggles.
Respirators
Wear positive pressure self-contained breathing apparatus (SCBA).
Small spills/leaks
Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. Cover with plastic sheet to prevent spreading. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. DO NOT GET WATER INSIDE CONTAINERS.
Stability
No data.

Fire.
Flash Point,°C
156
Fire fighting
Small Fires: Dry chemical, carbon dioxide or water spray. Large Fires: Water spray, fog or regular foam.
Fire potential
Combustible material: may burn but does not ignite readily.
Hazards
Containers may explode when heated.
Combustion products
Fire may produce irritating, corrosive and/or toxic gases.

Health.
Poison_Class
2
Exposure effects
The toxological properties of this substance have not been fully investigated.
   Inhalation
Highly toxic, may be fatal if inhaled, swallowed or absorbed through skin. Effects of contact or inhalation may be delayed.
   Skin
Contact with molten substance may cause severe burns to skin and eyes. Avoid any skin contact.
   Eyes
See Skin.

First aid
 
   Ingestion
Treat ingestions of greater than 40 milligrams per kilogram with decontamination of the stomach if within 4 hours of ingestion. Administer charcoal as a slurry.
   Inhalation
Move victim to fresh air. Apply artificial respiration if victim is not breathing. Do not use mouth-to-mouth method if victim ingested or inhaled the substance; induce artificial respiration with the aid of a pocket mask equipped with a one-way valve or other proper respiratory medical device. Administer oxygen if breathing is difficult.
   Skin
Remove and isolate contaminated clothing and shoes. Immediately flush with running water for at least 20 minutes. For minor skin contact, avoid spreading material on unaffected skin.
   Eyes
Immediately flush with running water for at least 20 minutes.

Transport.
UN number
2783
Response guide
Hazard class
6.1
Packing Group
I; II; III
 
USCG CHRIS Code
MPT
 
Std. Transport #
4921443