Material Safety Data Sheet: Magnesium Oxide

Identification

Product Name: Magnesium Oxide
Chemical Formula: MgO
Common Synonyms: Calcined magnesite, magnesia
Manufacturer Information: Found on packaging or supplier's reference document
Recommended Use: Industrial applications, laboratory chemical, refractory material, food additive, fertilizer input
Contact Numbers for Emergency: Supplier emergency phone and local poison control center
CAS Number: 1309-48-4

Hazard Identification

GHS Classification: Not classified as hazardous by GHS criteria for physical or health hazards
Status Under Various Standards: Not regulated as a hazardous substance for transport or workplace standards in most jurisdictions
Appearance: White or off-white odorless powder
Pictograms: None required
Signal Word: None
Hazard Statements: Possible irritation if dust contacts eyes or skin; inhaling dust may affect respiratory tract
Precautionary Statements: Avoid inhalation and contact, practice good hygiene after handling

Composition / Information on Ingredients

Chemical Name: Magnesium Oxide
Synonyms: Magnesia, periclase
CAS Number: 1309-48-4
EC Number: 215-171-9
Concentration: 100% for pure material, less if mixed with other ingredients in a product form
Impurities: Can contain trace amounts of calcium oxide, silicon dioxide depending on grade/source

First Aid Measures

Inhalation: Move person to fresh air, get medical help if symptoms like coughing or shortness of breath remain
Skin Contact: Remove contaminated clothing, wash area with soap and water
Eye Contact: Rinse open eyes with plenty of water for at least 15 minutes, get medical advice if redness or irritation stays
Ingestion: Rinse mouth with water, drink water to dilute, seek medical attention if uncomfortable
Special Considerations: Provide medical staff product label or SDS for reference

Fire-Fighting Measures

Suitable Extinguishing Media: Material itself is not flammable, use media suitable for fire in surrounding area such as water spray, dry powder, foam, or carbon dioxide
Hazards From Combustion: Magnesium oxide does not burn; thermal decomposition at extremely high temperature can release magnesium fumes
Protective Equipment: Standard fire-fighting gear, self-contained breathing apparatus for fire of significant size
Further Notes: Avoid breathing smoke, keep containers cool with water spray if exposed to fire

Accidental Release Measures

Personal Precautions: Avoid creating and breathing dust, wear proper protection for skin, eyes, respiratory system
Spill Control: Stop release if safe, sweep or use vacuum with HEPA filter, minimize dust generation
Environmental Precautions: Prevent entry into sewers or waterways, report major releases to authorities
Clean-up Methods: Collect into containers for disposal or recycling, wash spill area with water

Handling and Storage

Handling: Avoid handling in ways that generate dust, use local exhaust ventilation, wash hands after handling
Storage Conditions: Store in tightly closed containers in a cool, dry, well-ventilated space, keep away from acids and incompatible materials
Special Rules: Keep away from sources of water to prevent hardening or caking, store off floor
Packaging Materials: Use materials resistant to alkaline dusty compounds

Exposure Controls and Personal Protection

Occupational Exposure Limits: OSHA PEL: 15 mg/m³ (total dust), 5 mg/m³ (respirable dust); ACGIH TLV: 10 mg/m³ (inhalable particulates)
Engineering Controls: Use local ventilation, dust extraction at source, closed systems if practical
Personal Protection: Safety goggles or glasses, dust mask meeting NIOSH N95 standard or better, gloves for frequent or heavy contact, protective clothing if needed
Hygiene Measures: Wash hands after handling, do not eat or drink near product, change out of work clothing at end of shift

Physical and Chemical Properties

Appearance: Fine white or slightly off-white powder
Odor: Odorless
pH: 10.3 (10% suspension in water)
Melting Point: 2800°C
Boiling Point: Not applicable (sublimes at 3600°C)
Solubility: 0.0086 g/100 mL in water (sparingly soluble)
Density: 3.6 g/cm³
Flash Point: Not flammable
Partition Coefficient: Not applicable
Vapor Pressure: Not volatile
Evaporation Rate: Not applicable

Stability and Reactivity

Chemical Stability: Stable under most conditions, reacts with acids to form magnesium salts and water
Hazardous Reactions: Reacts with strong acids, moisture can cause clumping or hardening
Conditions to Avoid: Contact with damp environments for extended periods, contact with incompatible materials
Incompatible Materials: Strong acids, ammonium salts, interhalogens
Hazardous Decomposition Products: Magnesium fumes at very high temperatures

Toxicological Information

Routes of Exposure: Inhalation, eye contact, skin contact, ingestion
Acute Effects: Dust can irritate respiratory tract, eyes, skin; may cause coughing, redness or slight itching
Chronic Effects: No evidence of significant chronic toxicity from repeated low-level exposure
LD50 (oral, rat): > 3980 mg/kg
Carcinogenicity: Not classified as carcinogenic by IARC, NTP, OSHA
Other Effects: High dose ingestion can cause diarrhea or stomach upset, people with existing respiratory issues may experience aggravated symptoms

Ecological Information

Ecotoxicity: Low toxicity to aquatic life at environmental concentrations
Mobility in Soil: Low solubility; tends to remain in soil where applied
Persistence and Degradability: Non-volatile, breaks down slowly by natural processes into magnesium ions in soil and water
Bioaccumulation Potential: Does not bioaccumulate in organisms
Other Environmental Notes: Larger releases to water can temporarily alter water alkalinity or hardness

Disposal Considerations

Disposal Methods: Dispose in approved landfill site or according to local authority regulations
Waste Classification: Not considered hazardous waste under RCRA in the US
Precautions: Avoid creating or spreading dust during disposal, use sealed containers for transport to disposal facility
Recycling: Product can be recovered and reused depending on process and purity level

Transport Information

UN Number: Not regulated under UN transport codes
Shipping Name: Not classified as hazardous for road, rail, marine, or air transport
Transport Hazard Class: Not applicable
Packing Group: Not assigned
Special Precautions: Use sealed, robust containers to minimize spillage and dust, avoid mixing with acids in same shipment

Regulatory Information

OSHA Status: Not listed as hazardous under US OSHA Hazard Communication Standard
TSCA: Listed on the US Toxic Substances Control Act Inventory
SARA Title III: Not listed as an extremely hazardous substance
REACH: Registered, permitted for use in the EU for industrial and many consumer applications
WHMIS (Canada): Not controlled
Other Regulations: Always check national and local guidelines for workplace air, waste and transport this material
Labeling: No hazard symbol or warning required in most jurisdictions