Product Name: Methanesulphonic Anhydride
Chemical Formula: C2H4O5S2
CAS Number: 19949-65-0
Synonyms: Methanesulfonic acid anhydride, MS anhydride
Manufacturer: Refer to supplier contact information on packaging
Recommended Use: Laboratory chemicals, chemical synthesis
Restrictions on Use: Industrial use only, not for drug, food, or household applications
Emergency Contact: Refer to national poison control or chemical emergency response services
Classification: Corrosive to metals, skin corrosion/irritation category 1, serious eye damage category 1
Label Elements: Danger pictogram with corrosion symbol
Signal Word: Danger
Hazard Statements: Causes severe skin burns and eye damage, harmful if inhaled
Precautionary Statements: Avoid breathing dust or vapors, wear protective gloves/clothing/eye/face protection, wash thoroughly after handling
Other Potential Hazards: May cause respiratory irritation, reacts violently with water and moisture, produces toxic fumes under fire conditions
GHS Pictograms: Corrosion, Exclamation Mark
Routes of Exposure: Inhalation, skin contact, eye contact, ingestion
Chemical Name: Methanesulphonic anhydride
Concentration: ≥98%
Impurities: Trace methanesulfonic acid or water (<2%)
Molecular Weight: 174.16 g/mol
Common Impurities: None significant for safety assessment at trace levels
Hazardous Components: Contains no intentionally added components other than main substance
Eye Contact: Immediately flush eyes with plenty of water for at least 15 minutes, lifting eyelids occasionally, seek urgent medical attention, remove contact lenses if present and easy to do
Skin Contact: Remove contaminated clothing, rinse skin thoroughly with water for at least 15 minutes, wash area with soap, seek medical help for persistent irritation or burns
Inhalation: Move exposed person to fresh air, keep at rest in a position comfortable for breathing, if breathing difficulty persists or collapse occurs call emergency services, administer oxygen if instructed by medical personnel
Ingestion: Do not induce vomiting, rinse mouth with water, never give anything by mouth to an unconscious person, seek immediate medical attention
Most Important Symptoms/Effects: Severe irritation, redness, pain, burns on mucous membranes, risk of blindness, delayed pulmonary effects after inhalation
Note to Physician: Treat symptomatically, monitor for respiratory distress and supportive care as needed
Suitable Extinguishing Media: Carbon dioxide, dry chemical powder, alcohol-resistant foam
Unsuitable Extinguishing Media: Water jet (increases violent reaction, may spread corrosive vapors)
Specific Hazards: Reacts with water to produce heat and corrosive fumes, may release oxides of sulfur and carbon monoxide/dioxide under combustion
Special Protective Equipment: Wear full bunker gear, self-contained breathing apparatus, resistant suit
Firefighting Instructions: Evacuate area, cool containers with water spray from a safe distance, avoid direct contact with substance or contaminated runoff
Explosion Data: Non-flammable, not sensitive to static discharge, hazardous decomposition products if involved in a fire
Personal Precautions: Ventilate area, evacuate unnecessary personnel, wear acid-resistant gloves, full protective clothing, chemical splash goggles, face shield, and suitable respirator if risk of inhalation
Emergency Procedures: Restrict access until cleanup complete, avoid contact with product, ensure emergency showers and eyewash stations are accessible
Spill Cleanup Methods: Absorb with inert material (dry sand, vermiculite), contain spillage, collect residues in compatible acid-resistant container for disposal
Environmental Precautions: Avoid release to environment, prevent material from entering waterways, sewage, or soil
Disposal of Contaminated Materials: Dispose as hazardous waste in accordance with local regulations, label and seal all waste properly
Handling Precautions: Use only in well-ventilated areas, keep container tightly closed except during transfer, avoid inhalation and direct contact with liquid, handle under dry, inert atmosphere if possible
Hygiene Measures: Wash hands and exposed skin after use, change contaminated clothing promptly, do not eat, drink, or smoke during handling
Technical Measures: Ensure local exhaust ventilation, use corrosion-proof equipment and containers
Storage Conditions: Store in a cool, dry, well-ventilated area, away from heat sources and incompatible materials (strong bases, oxidizers, water/moisture), keep container tightly sealed
Packaging Materials: Use only containers and seals resistant to strong acids, glass or high-density polyethylene preferred
Exposure Limits: No established occupational exposure limits for methanesulphonic anhydride, minimize exposure as a best practice
Engineering Controls: Use of chemical fume hood or equivalent ventilation required for laboratory and industrial settings
Eye Protection: Chemical safety goggles and face shield
Skin Protection: Acid-resistant gloves (butyl rubber, neoprene, nitrile), long-sleeved laboratory coats or acid-resistant clothing
Respiratory Protection: Use approved respirator (organic vapor/acid gas cartridge) in case of inadequate ventilation or aerosol risk
Other Protection: Safety showers and eyewash stations within immediate reach, closed-toe shoes, avoid wearing contact lenses
Appearance: Colorless to pale yellow oily liquid
Odor: Pungent, sulfurous
Odor Threshold: Not determined
pH: <1 in aqueous solution
Melting/Freezing Point: Around 18–21 °C
Boiling Point: Approximately 138–140 °C at 17 mmHg
Flash Point: Not flammable
Evaporation Rate: Not determined
Flammability: Not classified as flammable
Vapor Pressure: Low at room temperature
Vapor Density: Not available
Solubility: Reacts exothermically with water, soluble in polar organic solvents
Partition Coefficient (n-octanol/water): Not determined
Auto-ignition Temperature: Not applicable
Decomposition Temperature: >160 °C
Viscosity: High, syrup-like
Density: 1.6–1.7 g/cm³ at 20 °C
Chemical Stability: Stable under recommended handling and storage conditions, reacts with water and alcohols
Reactivity: Hydrolyzes rapidly with water, forms corrosive methanesulfonic acid and heat
Possible Hazardous Reactions: Contact with bases or oxidizers may cause violent exothermic reactions
Conditions to Avoid: Moisture, open air, elevated temperatures
Incompatible Materials: Water, alcohols, bases, strong oxidizing agents, amines, metals sensitive to acid corrosion
Hazardous Decomposition Products: Sulfur oxides, carbon oxides, toxic and corrosive gases upon decomposition or combustion
Acute Toxicity: Harmful by inhalation, contact, and ingestion, corrosive to skin, eyes, and mucous membranes
Skin Corrosion/Irritation: Causes severe burns, laboratory tests indicate strong corrosive potential
Serious Eye Damage/Irritation: Causes blindness on contact, immediate pain and tissue destruction
Respiratory Sensitization: Not classified as respiratory sensitizer, but vapors can cause severe upper airway irritation and chemical pneumonitis in high concentrations
Chronic Effects: Prolonged or repeated exposure causes persistent skin or respiratory irritation, no reliable data on carcinogenicity or reproductive hazards
Symptoms of Exposure: Burning sensations, pain, redness, swelling, blistering, permanent tissue damage based on contact site
LD50/LC50 Values: Not well established for this compound, similar sulfonic anhydrides exhibit strong corrosivity at milligram levels
Medical Conditions Aggravated: Preexisting skin, eye, or respiratory disorders may worsen after exposure
Ecotoxicity: No direct testing data, related compounds exhibit harmful effects on aquatic organisms when released undiluted, acidification risk for aquatic habitats
Persistence and Degradability: Hydrolyzes rapidly in the environment to methanesulfonic acid, which is biodegradable but very acidic
Bioaccumulative Potential: Expected to have low potential for bioaccumulation, high water solubility and rapid degradation
Mobility in Soil: High mobility due to solubility, product migrates and reacts quickly with soil moisture
Other Adverse Effects: Large spills threaten soil and watershed acidity, neutralization required before disposal
Waste Generation: Collect residual and contaminated materials as hazardous chemical waste
Disposal Methods: Neutralize under supervision with basic solution and abundant water, avoid uncontrolled release, only dispose in accordance with local hazardous waste treatment regulations
Waste Container Requirements: Use acid-resistant, labeled containers with proper sealing
Waste Code: Subject to hazardous waste regulations depending on local and national requirements
Disposal of Packaging: Rinse empty containers with large volumes of water, treat rinseate as hazardous waste
UN Number: 3265
Proper Shipping Name: Corrosive liquid, acidic, organic, n.o.s. (contains methanesulphonic anhydride)
Transport Hazard Classes: 8 (Corrosive substances)
Packing Group: II (substantial danger)
Marine Pollutant: Not listed as marine pollutant but acidification is a risk
Land Transport (ADR/RID): Regulated as corrosive hazardous material
Air Transport (ICAO/IATA): Prohibited from passenger aircraft, limited cargo quantities with strict packaging
Special Transport Precautions: Protect from moisture, segregate from incompatible cargo, check national exceptions and restrictions
Classification: Subject to regulations for hazardous chemical substances (e.g., EU REACH, OSHA Hazard Communication Standard, US TSCA)
Label Requirements: GHS signal words and hazard statements, use of corrosion pictograms and PPE specifications mandated
Inventory Listings: Present or eligible for major international chemical inventories (Contact supplier for up-to-date inventory status)
Restrictions: Regulated as laboratory and industrial chemical, not listed as SARA Title III Extremely Hazardous Substance or CERCLA hazardous material, not under controlled substances
Other Regulatory Notes: Employer training and exposure monitoring required where handled, import/export may require government notification or authorization
