Methyl isocyanate

  • Isocyanatomethane
  • Isocyanic acid, methyl ester
  • Methyl ester of isocyanic acid
  • MIC
Formula
CH3NCO
Structure

Registry Numbers and Inventories.
CAS
624-83-9
EC (EINECS/ELINCS)
210-866-3
EC Index Number
615-001-00-7
EC Class
Extremely flammable; Toxic; Irritant
RTECS
NQ9450000
RTECS class
Mutagen; Reproductive Effector; Human Data; Primary Irritant
UN (DOT)
2480
Merck
12,6163
Beilstein/Gmelin
605318
Beilstein Reference
4-04-00-00247
RCRA
P064
Swiss Giftliste 1
G-2470
Canada DSL/NDSL
NDSL
US TSCA
Listed
Austrailia AICS
Listed

Properties.
Formula
C2H3NO
Formula mass
57.05
Melting point, °C
-80
Boiling point, °C
39
Vapor pressure, mmHg
531 (25 C)
Vapor density (air=1)
~2
Critical temperature
218
Critical pressure
55
Density
0.9744 g/cm3 (15 C)
Solubility in water
100 g/L
Refractive index
1.3718 (14.9 C)
Partition coefficient, pKow
0.83
Heat of vaporization
26.8 kJ/mol
Heat of combustion
-1128 kJ/mol

Hazards and Protection.
Storage
Keep cool, no sparks, flames. Store in areas separated from oxidizers. store in stainless steel receptacles, nickel, or perfectly vitrified materials.
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
Keep sparks, flames, and other sources of ignition away. Keep material out of water sources and sewers. Build dikes to contain flow as necessary. Attempt to stop leak if without undue personnel hazard. Use water spray to knock-down vapors.
Stability
Exploded violently when dropped on hot surface. Dried out material may explode if exposed to heat, flame, or shock. Runoff to sewer may create fire or explosion hazard.
Incompatibilities
Reacts rapidly with acids and bases (including amines) Attacks some plastics, rubbers, and coatings.

Fire.
Flash Point,°C
-7
Autoignition, °C
534
Upper exp. limit, %
26
Lower exp. limit, %
5.3
Fire fighting
Material is extremely hazardous to health but areas may be entered with extreme care. Full protective clothing, including self-contained breathing apparatus (coat, pants, gloves, boots, and bands around legs, arms and waist) should be provided. No skin surface should be exposed. Stay away from ends of tanks. Do not get water inside container. Spray cooling water on containers that are exposed to flames until well after fire is out. Withdraw immediately in case of rising sound from venting safety device or any discoloration of tank due to fire.Small fires: dry chemical, carbon dioxide, water spray, or foam. Large fires: water spray, fog, or foam.
Fire potential
Very flammable.
Hazards
May be ignited by heat, sparks, or flames. Vapors may travel to a source of ignition and flash back. Container may explode violently in heat of fire. Vapor explosion and poison hazard indoors, outdoors, or in sewers.
Combustion products
Methyl isocyanate vapors and hydrogen cyanide will be emitted in a fire.
Health
4
 
Flammability
3
 
 
Reactivity
2
 
 
Special
W

Health.
Exposure limit(s)
NIOSH REL: TWA 0.02 ppm (0.05 mg/m3)[skin] OSHA PEL: TWA 0.02 ppm (0.05 mg/m3) [skin] IDLH 3 ppm
Poison_Class
1
Exposure effects
Acute exposure may cause dyspnea. Pulmonary edema-induced hypoxia may produce CNS depression. There is conflicting data as to whether methyl isocyanate is fetotoxic, however, it crosses the placental barrier. Reports from Bhopal, India and animal studies suggest a high degree of adverse reproductive effects and teratogenicity.
   Ingestion
Gastrointestinal irritation and vomiting may occur.
   Inhalation
TOXIC; inhalation, ingestion or contact (skin, eyes) with vapors, dusts or substance may cause severe injury, burns, or death. Effects may be delayed.
   Skin
Skin irritation is likely. Contact can cause chemical burns (sittig, 1991; hsdb, 2001).
   Eyes
Contact with the eye is extremely irritating and may cause permanent damage with cataract formation, trachoma and chronic blepharitis.

First aid
 
   Ingestion
Administer charcoal as a slurry (240 ml water/30 g charcoal). Usual dose: 25 to 100 g in adults/adolescents.
   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
2480
Response guide
Hazard class
6.1
PRTC
T
Packing Group
I
 
USCG CHRIS Code
MIS
 
Std. Transport #
4927009