Chemical Name: Methanesulphonic Acid
Synonyms: MSA, Methanesulfonic acid
CAS Number: 75-75-2
Recommended Use: Acid catalyst, electroplating, cleaning agent, pharmaceutical intermediate
Supplier Details: Manufacturer or supplier address and emergency contact (usually listed on transportation paperwork)
Emergency Contact Number: Refer to internal safety protocol or poison control center
Product Code: Stated by manufacturer
Hazard Class: Corrosive to metals and tissue, classified as a strong acid
GHS Label Elements: Signal word: Danger
Pictograms: Corrosive symbol and exclamation mark required on containers
Hazard Statements: Causes severe skin burns and serious eye damage; harmful if inhaled or swallowed; may cause respiratory irritation
Precautionary Statements: Wear protective clothing, prevent contact with skin or eyes, avoid inhaling vapors or mists
Other Hazards: Reacts violently with water or bases, releases heat and fumes on contact with metals
Chemical Ingredient: Methanesulphonic Acid
Concentration: Approx. 98–100%, can be diluted by user
Impurities: Trace amounts of sulfur dioxide, water, possible trace organics from manufacturing
Molecular Formula: CH4O3S
Molecular Weight: 96.10 g/mol
Eye Contact: Immediately flush eyes with plenty of water for at least 15 minutes, removing contact lenses if present. Get medical help at once.
Skin Contact: Remove contaminated clothing, rinse affected skin with plenty of water for at least 15 minutes. Seek medical attention for burns or persistent irritation.
Inhalation: Remove person to fresh air, keep at rest, provide warmth. Get medical help if breathing is difficult.
Ingestion: Rinse mouth with water, do not induce vomiting, seek immediate medical advice.
Notes to Physician: Treat symptomatically; consider delayed pulmonary edema and corrosive effects.
Suitable Extinguishing Media: Use water spray, dry chemical, carbon dioxide, or alcohol-resistant foam. Water jet not advised due to risk of chemical reaction.
Specific Hazards: Acid vapors and toxic gases (sulfur oxides) may form in fire. Containers can rupture under intense heat.
Protective Equipment for Firefighters: Full protective gear and self-contained breathing apparatus recommended.
Advice for Firefighters: Cool containers with water spray from a safe distance; avoid runoff that may pollute waterways.
Personal Precautions: Wear acid-resistant gloves, apron, safety goggles, and respiratory protection if vapors are present.
Environmental Precautions: Prevent spills from entering sewers or waterways. Notify environmental authorities in case of large spills.
Containment and Cleanup: Neutralize with sodium bicarbonate or lime, use non-combustible absorbent material (vermiculite, sand); collect and dispose of following regulations. Ventilate area.
Emergency Procedures: Evacuate unnecessary personnel from area, use diking to stop spread.
Handling: Keep containers tightly closed, handle in well-ventilated areas away from incompatibles such as bases, strong oxidizers, and reducing agents. Use only with corrosion-resistant equipment.
Storage: Store in containers made of materials compatible with corrosive acids, such as glass or certain plastics. Do not use metal shelves or containers. Keep away from direct sunlight, water, and sources of ignition.
Other Precautions: Segregate from food and feedstuffs. Keep emergency showers and eyewash stations nearby.
Occupational Exposure Limits: No specific OSHA, ACGIH, or NIOSH limits assigned; monitor for respiratory and skin irritation.
Engineering Controls: Use local exhaust ventilation or chemical fume hoods to maintain concentrations below exposure guidelines.
Eye Protection: Wear chemical safety goggles or face shield
Skin Protection: Use acid-resistant gloves and protective clothing (aprons, sleeves)
Respiratory Protection: If airborne concentrations exceed recommended limits, use acid vapor respirators or supplied-air respirators.
Hygiene Measures: Wash hands and forearms after handling, remove contaminated clothing before entering eating areas.
Appearance: Colorless to pale yellow liquid
Odor: Slight sulfurous
pH: Less than 1 (strongly acidic)
Melting Point: 20 °C (68 °F)
Boiling Point: 167 °C (333 °F) at 760 mmHg
Flash Point: Not flammable under normal conditions
Evaporation Rate: Not applicable
Vapor Pressure: 0.2 mmHg at 25 °C
Vapor Density: 3.3 (air = 1)
Solubility: Completely miscible with water; exothermic reaction
Density: 1.48 g/cm3 at 20 °C
Partition Coefficient: Not determined
Viscosity: 1.28 cP at 20 °C
Chemical Stability: Stable under recommended conditions of storage
Incompatible Materials: Strong bases, oxidizing agents, reducing agents, water (generates heat), metals (produces hydrogen)
Conditions to Avoid: Heat, moisture, exposure to metals, sources of ignition
Hazardous Decomposition Products: Sulfur oxides, methanesulfonate fumes can form during heating
Polymerization: Not known to occur
Acute Toxicity: Oral LD50 (rat): approximately 1600 mg/kg
Skin Corrosion: Causes severe burns
Eye Damage: Permanent damage possible with direct exposure
Inhalation: Burning of respiratory tract, coughing, choking, possible pulmonary edema
Chronic Effects: Prolonged exposure causes dermatitis or ulceration
Carcinogenicity: Not listed as a carcinogen by IARC, NTP, or OSHA
Reproductive Toxicity: Not established, insufficient data
Sensitization: Not established
Other Data: Methanesulphonic acid hydrolyzes to less toxic forms in the body and the environment
Ecotoxicity: Harmful to aquatic organisms due to pH shift
Persistence and Degradability: Biodegradable; breaks down fully in water under normal environmental conditions
Bioaccumulation: Low potential for bioaccumulation
Mobility in Soil: Highly mobile in water; acidifies water and soil
Other adverse effects: Release to water or soil requires environmental review; rapid neutralization with base mitigates hazard
Disposal Methods: Neutralize with suitable base (sodium carbonate or calcium hydroxide) before disposal. Dilute and flush to drain only where permitted by regulations.
Container Disposal: Triple rinse with water before recycling or disposal. Never reuse unclean containers for food or drink.
Local Legislation: Must follow federal, state, and local hazardous waste disposal requirements
Precautions: Ensure complete neutralization, prevent release to natural water bodies. Use licensed waste treatment contractors as required by authorities.
UN Number: 3265
Proper Shipping Name: Corrosive Liquid, Acidic, Organic, N.O.S. (Methanesulphonic Acid)
Transport Hazard Class: 8 (Corrosive substances)
Packing Group: II (medium danger)
Environmental Hazards: Not classified as marine pollutant, but strong acid hazards remain
Special Precautions: Containers must be clearly labeled and secured. Emergency spill kits should be present during transit.
Transport Regulations: Comply with DOT (US), IMDG (sea), IATA (air) guidelines for corrosive substances.
US Federal Regulations: Ingredient not specifically listed under TSCA, RCRA, SARA Title III Section 313
European Union: Classified under CLP Regulation (EC) No 1272/2008, REACH registration required
Global Inventory Status: Listed in TSCA (US), EINECS (EU), DSL (Canada), AICS (Australia), ENCS (Japan)
Labeling Requirements: Must carry hazard/danger statements, pictograms, and precautionary advice as required by the country or region
Worker Safety Directives: Employers must provide training on safe handling, storage, and emergency response
