Methyl iodide
Synonyms & Trade Names
Iodomethane, MonoiodomethaneExposure Limits
NIOSH REL
Ca TWA 2 ppm (10 mg/m3) [skin] See Appendix AOSHA PEL
TWA 5 ppm (28 mg/m3) [skin]Physical Description
Colorless liquid with a pungent, ether-like odor. [Note: Turns yellow, red, or brown on exposure to light & moisture.]Molecular Weight
141.9Boiling Point
109°FFreezing Point
-88°FSolubility
1%Vapor Pressure
400 mmHgIonization Potential
9.54 eVSpecific Gravity
2.28Flash Point
NAUpper Exposive Limit
NALower Explosive Limit
NA
Noncombustible Liquid
Incompatibilities & Reactivities
Strong oxidizers [Note: Decomposes at 518°F.]Exposure Routes
inhalation, skin absorption, ingestion, skin and/or eye contactSymptoms
irritation eyes, skin, respiratory system; nausea, vomiting; dizziness, ataxia; slurred speech, drowsiness; dermatitis; [potential occupational carcinogen]Target Organs
Eyes, skin, respiratory system, central nervous systemCancer Site
[in animals: lung, kidney & forestomach tumors]Personal Protection/Sanitation
(See protection codes)Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated
Remove:When wet or contaminated
Change:No recommendation
Provide:Eyewash, Quick drench
First Aid
(See procedures)Eye:Irrigate immediately
Skin:Soap flush immediately
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations
NIOSH
At concentrations above the NIOSH REL, or where there is no REL, at any detectable concentration:
(APF = 10,000) Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode
(APF = 10,000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained positive-pressure breathing apparatus
Escape:
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister
Any appropriate escape-type, self-contained breathing apparatus
- Page last reviewed:April 11, 2016
- Page last updated:April 11, 2016
- Content source:
- National Institute for Occupational Safety and Health (NIOSH) Education and Information Division