- as-Dimethyl sulfite
- as-Dimethyl sulphite
- Methyl mesylate
- Methylmethane sulfonate
- Methyl methanesulfonic acid
Colorless to amber liquid.
Registry Numbers and Inventories.
Agricultural Chemical and Pesticide; Tumorigen; Drug; Mutagen; Reproductive Effector
Melting point, °C
Boiling point, °C
Vapor pressure, mmHg
0.42 (25 C)
1.3206 g/cm3 (0 C)
Solubility in water
1.41248 (16.2 C)
Partition coefficient, pKow
Heat of vaporization
Hazards and Protection.
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.
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.
If Tyvek-type disposable protective clothing is not worn during handling of this chemical, wear disposable Tyvek-type sleeves taped to your gloves.
Wear a NIOSH/MSHA or European Standard EN 149 approved full-facepiece airline respirator in the positive pressure mode with emergency escape provisions.
Absorb spill with inert material, (e.g., dry sand or earth), then place into a chemical waste container.
Stable under normal temperatures and pressures.
Strong oxidizing agents - strong acids - strong bases.
Carbon monoxide, oxides of sulfur, carbon dioxide.
Fires involving this material can be controlled with a dry chemical, carbon dioxide or Halon extinguisher.
This chemical is combustible.
Contact with metals may evolve flammable hydrogen gas.
Fire may produce irritating, corrosive and/or toxic gases.
I-2A, N-2, CP65
Symptoms of exposure to this compound may include irritation of the eyes, skin, mucous membranes, nose and respiratory tract. It can cause dermatitis and nausea. Large doses ingested over nearly a year produced gastrointestinal and hepatic toxic effects.
Do NOT induce vomiting. Allow the victim to rinse his mouth and then to drink 2-4 cupfuls of water, and seek medical advice.
Remove from exposure to fresh air immediately.
Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes.
First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.
I; II; III