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METHYL IODIDE
ICSC: 0509
Peer-Review Status: 08.06.2012 Validated
Iodomethane 
CAS #: 74-88-4 RTECS #: PA9450000
UN #: 2644
EC #: 602-005-00-9
EINECS #: 200-819-5
    Formula: CH3I
Molecular mass: 142.0

TYPES OF
HAZARD /
EXPOSURE
ACUTE HAZARDS / SYMPTOMS      PREVENTION      FIRST AID / FIRE FIGHTING
FIRE Not combustible. Gives off irritating or toxic fumes (or gases) in a fire.    In case of fire in the surroundings, use appropriate extinguishing media. 
EXPLOSION     In case of fire: keep drums, etc., cool by spraying with water. 
 
EXPOSURE   STRICT HYGIENE!  IN ALL CASES CONSULT A DOCTOR! 
Inhalation Cough. Sore throat. Nausea. Vomiting. Diarrhoea. Headache. Dizziness. Drowsiness. Weakness. Convulsions. Confusion. Death Symptoms may be delayed. See Notes.  Use ventilation, local exhaust or breathing protection.  Fresh air, rest. Refer immediately for medical attention. 
Skin Redness. Pain.  Protective gloves. Protective clothing.  Remove contaminated clothes. Rinse and then wash skin with water and soap. Refer for medical attention . 
Eyes Redness. Pain.  Wear safety goggles or eye protection in combination with breathing protection.  First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention. 
Ingestion See Inhalation.  Do not eat, drink, or smoke during work.  Rinse mouth. Do NOT induce vomiting. Give a slurry of activated charcoal in water to drink. Refer immediately for medical attention. 

SPILLAGE DISPOSAL
PACKAGING & LABELLING
Evacuate danger area! Consult an expert! Personal protection: self-contained breathing apparatus. Collect leaking and spilled liquid in sealable containers as far as possible. Absorb remaining liquid in sand or inert absorbent. Then store and dispose of according to local regulations.  Unbreakable packaging.
Put breakable packaging into closed unbreakable container.
Do not transport with food and feedstuffs. 
EC Classification
Symbol: T; R: 21-23/25-37/38-40; S: (1/2)-36/37-38-45 
UN Classification
UN Hazard Class: 6.1; UN Pack Group: I 
GHS Classification
Signal: Danger
Toxic if swallowed or if inhaled
Causes skin irritation
Causes serious eye irritation
Causes damage to central nervous system if inhaled
Very toxic to aquatic life with long lasting effects 
skull;toxiccancer;health hazenviro;aqua

EMERGENCY RESPONSE SAFE STORAGE
  Provision to contain effluent from fire extinguishing. Separated from strong oxidants and food and feedstuffs. Well closed. Ventilation along the floor. Store in an area without drain or sewer access. 

IMPORTANT DATA
Physical State; Appearance
COLOURLESS LIQUID WITH CHARACTERISTIC ODOUR. TURNS BROWN ON EXPOSURE TO LIGHT AND MOISTURE. 

Physical dangers
The vapour is heavier than air and may accumulate in lowered spaces causing a deficiency of oxygen. 

Chemical dangers
Decomposes above 270°C . This produces hydrogen iodide. Reacts with strong oxidants. This generates explosion hazard. Reacts with oxygen at 300°C. This generates explosion hazard. 

Occupational exposure limits
TLV: 2ppm as TWA; (skin); (ACGIH 2011).
MAK: Carcinogen category: 2; Skin absorption (H); (DFG 2011). 

Routes of exposure
The substance can be absorbed into the body by inhalation of its vapour and by ingestion. 

Inhalation risk
A harmful contamination of the air can be reached very quickly on evaporation of this substance at 20°C. 

Effects of short-term exposure
The substance is irritating to the eyes, skin and respiratory tract. The substance may cause effects on the central nervous system. The effects may be delayed. Medical observation is indicated. 

Effects of long-term or repeated exposure
Tumours have been detected in experimental animals but may not be relevant to humans. 


PHYSICAL PROPERTIES ENVIRONMENTAL DATA
Boiling point: 42.5°C
Melting point: -66.5°C
Relative density (water = 1): 2.3
Solubility in water, g/100ml at 20°C: 1.4
Vapour pressure, kPa at 20°C: 50
Relative vapour density (air = 1): 4.9
Relative density of the vapour/air-mixture at 20°C (air = 1): 2.7
Octanol/water partition coefficient as log Pow: 1.51
Viscosity: 0.18 mm^2/sec at 40°C
Explosive limits, vol% in air: 8.5 - 66%
Auto-ignition temperature: 355°C  
The substance is very toxic to aquatic organisms. This substance does enter the environment under normal use. Great care, however, should be taken to avoid any additional release, for example through inappropriate disposal. 

NOTES
The symptoms of acute poisoning do not become manifest until hours or even days after exposure, and they are aggravated by physical effort. 

ADDITIONAL INFORMATION
 

IPCS
International
Programme on
Chemical Safety
WHO ILO EC Prepared in the context of cooperation between the International Programme on Chemical Safety and the European Commission
© IPCS 2004-2012
LEGAL NOTICE Neither the EC nor the IPCS nor any person acting on behalf of the EC or the IPCS is responsible for the use which might be made of this information.


    See Also:
       Toxicological Abbreviations
       Methyl iodide (PIM 341F, French)
       Methyl Iodide  (IARC Summary & Evaluation, Volume 15, 1977)
       Methyl Iodide  (IARC Summary & Evaluation, Volume 41, 1986)
       Methyl Iodide  (IARC Summary & Evaluation, Volume 71, 1999)