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Product Name: Mercurous Oxide
Chemical Formula: Hg2O
CAS Number: 21908-53-2
Synonyms: Mercury(I) Oxide, Yellow Mercury Oxide
Manufacturer: Contact local supplier or chemical provider
Recommended Use: Laboratory reagent, chemical synthesis
Restrictions: Avoid use for pharmaceutical or food applications
Emergency Phone: Refer to local emergency numbers or poison control
Classification: Acute toxicity Oral (Category 2), Skin corrosion/irritation (Category 2), Acute aquatic hazard (Category 1), Chronic aquatic hazard (Category 1)
Label Elements: Skull and Crossbones symbol, Environmental hazard symbol
Signal Word: Danger
Hazard Statements: Fatal if swallowed or inhaled. Toxic in contact with skin. Causes skin and eye irritation. Very toxic to aquatic life with long lasting effects.
Precautionary Statements: Avoid breathing dust or fumes. Avoid release to the environment. Wear protective gloves and eye protection. Wash hands thoroughly after handling. Do not eat, drink, or smoke when using this product.
Name: Mercurous Oxide
Concentration: 100%
Chemical Identity: Mercury monoxide
Molecular Weight: 432.6 g/mol
Impurities: Trace mercury(II) compounds or elemental mercury possible in technical grades
Inhalation: Move exposed person to fresh air. Maintain breathing and keep comfortable. Seek immediate medical attention.
Skin Contact: Remove contaminated clothing and wash skin thoroughly with soap and plenty of water. Medical attention is strongly advised due to mercury absorption.
Eye Contact: Rinse eyes with plenty of water for several minutes, lifting lids occasionally. Remove contact lenses if present. Seek medical care right away.
Ingestion: Rinse mouth immediately. Do not induce vomiting. Seek immediate medical help.
Notes for Physicians: Treatment is symptomatic. Consider chelation therapy and monitor for acute mercury toxicity effects on the kidneys and central nervous system.
Suitable Extinguishing Media: Use water spray, foam, dry chemical powder, or CO2.
Unsuitable Media: Never use straight water stream; avoid high-pressure hoses.
Hazardous Combustion Products: Mercury vapor, mercury oxides.
Special Protective Equipment: Firefighters should wear self-contained breathing apparatus and full protective gear.
Advice: Remove chemically contaminated clothing quickly. Do not allow run-off to enter sewers or waterways.
Personal Precautions: Avoid direct contact. Wear respiratory protection, gloves, protective clothing, and eye protection. Use only with trained personnel in a controlled area.
Environmental Precautions: Prevent spill from entering drains, waterways, or soil.
Cleanup Methods: Collect spilled material with non-combustible absorbent such as sand or earth. Do not use materials containing ammonium compounds. Store and dispose of waste as hazardous.
Decontamination: Ventilate the area thoroughly after cleanup. Wash surfaces with suitable mercury decontaminant. Monitor air and surfaces for residual contamination.
Handling: Handle only in well-ventilated areas or chemical fume hood. Keep container closed. Avoid creation of dust and inhalation of vapors.
Storage: Store in tightly sealed original containers, away from heat, moisture, acids, and reducing agents. Keep away from food and feed.
Incompatible Materials: Ammonia, acetylenes, strong acids, halogens, and organic materials.
Additional Considerations: Label containers clearly. Regularly inspect storage area for leaks or damage.
Engineering Controls: Work in an exhaust-ventilated area. Use fume hoods or local mechanical ventilation.
Exposure Limits: OSHA PEL: 0.1 mg/m3 (as mercury); ACGIH TLV: 0.025 mg/m3 (as mercury)
Personal Protective Equipment: Respirator with mercury vapor cartridges, chemical-resistant gloves (nitrile or PVC), safety goggles, full protective lab coat.
Hygiene Measures: Wash hands and exposed skin thoroughly after use. No eating, drinking, or smoking in work area.
Environmental Controls: Collect and treat waste with approved mercury recovery systems or send to licensed disposal facility.
Appearance: Orange-yellow or brownish-red powder
Odor: Odorless
pH: Not applicable (insoluble in water)
Melting Point: Decomposes at around 500°C, no true melting point
Boiling Point: Not applicable (decomposes)
Solubility in Water: Insoluble
Density: About 9.7 g/cm3
Vapor Pressure: Negligible at room temperature
Partition Coefficient: Not available
Other Properties: Decomposes to elemental mercury and oxygen with heat
Chemical Stability: Unstable in light, heat, or on contact with reducing agents.
Incompatible Materials: Ammonia, reducing agents, strong acids, acetylene, chlorine, bromine.
Hazardous Decomposition: Produces elemental mercury vapor and oxygen gas.
Polymerization: Will not occur.
Specific Conditions: Store away from sunlight and prevent exposure to open flames or high temperature sources.
Acute Effects: Extremely toxic by inhalation, ingestion, or skin absorption. Causes irritation and damage to skin and mucous membranes.
Chronic Effects: Long-term exposure may lead to kidney damage, central nervous system effects, and behavioral changes. Repeated exposure increases risk of mercury accumulation in the body.
Symptoms: Nausea, vomiting, diarrhea, abdominal pain, tremors, memory disturbance, peripheral neuropathy.
Carcinogenicity: Not classified as carcinogen but chronic mercury exposure linked to organ damage.
Other Data: Embryotoxic, teratogenic, may harm fertility. Genotoxic effects reported in some studies.
Ecotoxicity: Very toxic to aquatic organisms and ecosystems even at low concentrations.
Persistence: Mercury compounds persist in soil and aquatic environments; capable of bioaccumulation and biomagnification in food webs.
Mobility: Insoluble in water; does not migrate readily in soil but may convert to more mobile forms through chemical reactions.
Aquatic Effects: Lethal to fish, invertebrates, and can disrupt reproductive cycles.
Other Harms: Mercury cycles through air, water, and soil, leading to global pollution concerns; controls and disposal are essential to prevent ecosystem damage.
Waste Treatment: Treat as hazardous waste under local, national, and international regulations. Use certified mercury recovery or stabilization processes.
Container Disposal: Containers must be decontaminated or disposed of as hazardous waste. Reuse without proper decontamination strongly discouraged.
Do Not: Dump in drains, sewers, or the environment.
Recommended Disposal: Send waste to licensed hazardous waste facility. Store waste securely until taken by authorized transporter.
Regulations: U.S. RCRA hazardous waste number D009; consult local and international requirements.
UN Number: UN1641
Shipping Name: Mercurous Oxide
Hazard Class: 6.1 (Toxic substance)
Packing Group: II
Label: Toxic
Special Precautions: Secure packaging to prevent breakage and spills. Avoid transport with incompatible chemicals such as acids and ammonium compounds. Comply with local, state, and federal regulatory transport rules.
Environmental Hazards: Marine pollutant – special handling required to prevent water contamination.
U.S. Regulations: Subject to the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), Resource Conservation and Recovery Act (RCRA), Toxic Substances Control Act (TSCA), and Emergency Planning and Community Right-to-Know Act (EPCRA). SARA Title III Section 313 requires notification for releases above reportable quantities.
International Regulations: Covered by the Minamata Convention on Mercury. European Union REACH-listed. Controlled under United Nations transport and chemicals conventions.
Workplace Limits: OSHA/NIOSH/ACGIH exposure limits apply in occupational settings.
Labeling: Requires hazard pictograms and precautionary statements under Globally Harmonized System (GHS).
