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Dimethyl sulfate

Synonyms & Trade Names
Dimethyl ester of sulfuric acid, Dimethylsulfate, Methyl sulfate
CAS No.
77-78-1
RTECS No.
DOT ID & Guide
1595 156
Formula
(CH₃)₂SO₄
Conversion
1 ppm = 5.16 mg/m3
IDLH
Ca [7 ppm]
See: 77781
Exposure Limits
NIOSH REL
Ca TWA 0.1 ppm (0.5 mg/m3) [skin] See Appendix A
OSHA PEL
TWA 1 ppm (5 mg/m3) [skin] See Appendix G
Measurement Methods
NIOSH 2524
See: NMAM or OSHA Methods
Physical Description
Colorless, oily liquid with a faint, onion-like odor.
Molecular Weight
126.1
Boiling Point
370°F (Decomposes)
Freezing Point
-25°F
Solubility
(64°F): 3%
Vapor Pressure
0.1 mmHg
Ionization Potential
?
Specific Gravity
1.33
Flash Point
182°F
Upper Explosive Limit
?
Lower Explosive Limit
?
Class IIIA Combustible Liquid: Fl.P. at or above 140°F and below 200°F.
Incompatibilities & Reactivities
Strong oxidizers, ammonia solutions [Note: Decomposes in water to sulfuric acid; corrosive to metals.]
Exposure Routes
inhalation, skin absorption, ingestion, skin and/or eye contact
Symptoms
irritation eyes, nose; headache; dizziness; conjunctivitis; photophobia (abnormal visual intolerance to light); periorbital (situated around the eye) edema; dysphonia, aphonia, dysphagia, productive cough; chest pain; dyspnea (breathing difficulty), cyanosis; vomiting, diarrhea; dysuria; analgesia; fever; proteinuria, hematuria (blood in the urine); eye, skin burns; delirium; [potential occupational carcinogen]
Target Organs
Eyes, skin, respiratory system, liver, kidneys, central nervous system
Cancer Site
[in animals: nasal & lung cancer]
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:Water 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 canister providing protection against the compound of concern
Any appropriate escape-type, self-contained breathing apparatus

Important additional information about respirator selection

See also
INTRODUCTION   ICSC CARD: 0148   MEDICAL TESTS: 0084
Page last reviewed: October 30, 2019