Calcium Tungstate Material Safety Data Sheet (MSDS)

Identification

Product Name: Calcium Tungstate
Synonyms: Scheelite, Calcium Wolframate
Chemical Formula: CaWO₄
CAS Number: 7789-75-5
Recommended Uses: X-ray screens, luminous paints, scintillation detectors, phosphors, ceramics, analytical reagent, metallurgy
Manufacturer: Detailed data from supplier or manufacturer required for contact in emergencies
Emergency Contact: Refer to manufacturer's emergency phone line or local poison control

Hazard Identification

GHS Classification: Not considered hazardous according to OSHA Hazard Communication Standard
Health Hazards: Dust may cause mechanical irritation to eyes, skin, and respiratory system
Physical Hazards: Nonflammable, stable under normal conditions
Environmental Hazards: Limited evidence of aquatic or soil toxicity, but spills can impact local environments
Signal Word: None
Hazard Statements: Prolonged inhalation of dust can irritate respiratory tract
Precautionary Statements: Wear appropriate personal protection when handling bulk powder, use dust control procedures

Composition / Information on Ingredients

Chemical Name: Calcium Tungstate
Common Name: Scheelite
Concentration: > 99%
Main Components: Calcium (Ca), Tungsten (W), Oxygen (O)
Impurities: Trace elements (silicon, iron, sodium, potassium) possible depending on provenance

First Aid Measures

Eye Contact: Rinse thoroughly with water for several minutes. Remove contact lenses if present. Seek medical attention for prolonged irritation.
Skin Contact: Wash area with soap and water. Remove contaminated clothing. Seek medical advice if irritation or rash develops.
Inhalation: Move to fresh air immediately. Support breathing as needed. Get medical advice if coughing or shortness of breath persist.
Ingestion: Rinse mouth out. Give water to drink. Get medical help if large quantities swallowed or symptoms develop.
Most Important Symptoms: Irritation to mucus membranes, respiratory discomfort
Advice to Physician: Treat symptomatically, no known specific antidote

Fire-Fighting Measures

Suitable Extinguishing Agents: Material is non-combustible. Extinguishing media for surrounding fire – water spray, CO₂, foam, or dry chemical
Unusual Hazards: On intense heat, may give off tungsten oxides and calcium oxides
Protective Equipment for Firefighters: Wear full protective gear and self-contained breathing apparatus in confined spaces
Advice for Firefighting: Move material from fire area if safe, prevent runoff from entering drains, dike fire control water

Accidental Release Measures

Personal Precautions: Use goggles and respiratory protection when handling powder or in case of dusty spill
Environmental Precautions: Minimize spillage into soil, drains, and waterways. Collect spillage for recovery or disposal
Cleanup Methods: Scoop up and place in suitable, labeled containers for reclamation or disposal. Use techniques that minimize dust. Wet clean area if possible
Emergency Procedures: Seek advice from local authorities if major spill, evacuate area if dust cloud possible

Handling and Storage

Precautions for Safe Handling: Process containers gently to avoid dust. Use local exhaust or dust collection
Hygiene Measures: Wash hands after handling. Remove clothing if contaminated
Storage Conditions: Keep tightly sealed in dry, cool, ventilated areas. Store away from incompatible materials – strong acids, oxidizers.
Incompatible Materials: Acids, strong bases, oxidizing agents which may react to release hazardous gases or compounds
Packaging Requirements: Store in containers resistant to corrosion and labeled correctly

Exposure Controls and Personal Protection

Exposure Limits: OSHA/ACGIH do not list specific exposure limits for Calcium Tungstate; use limits for nuisance dust – 10 mg/m³ (total), 5 mg/m³ (respirable fraction)
Engineering Controls: Local exhaust ventilation, process enclosures, and dust collection
Personal Protective Equipment (PPE): Dust-proof goggles, gloves, lab coats, and approved respirators if dust levels exceed limits
Hygiene: Wash hands before eating or smoking, shower after handling large quantities
Environmental Controls: Prevent dust accumulation on surfaces, regularly clean work areas

Physical and Chemical Properties

Appearance: White or off-white crystalline powder
Odor: Odorless
Molecular Weight: 287.92 g/mol
Melting Point: 1625°C
Boiling Point: Not applicable
Solubility: Insoluble in water, soluble in concentrated acids
Vapor Pressure: Not applicable
Density: 6.06 g/cm³ at 20°C
pH: Neutral (in water suspension)
Partition Coefficient: No data
Decomposition Temperature: Above 1625°C releases oxides of tungsten and calcium

Stability and Reactivity

Chemical Stability: Stable under normal use and storage conditions
Reactivity: Low reactivity; reacts with strong acids releasing soluble tungstate
Conditions to Avoid: Excess heat, moisture, contact with incompatible chemicals
Incompatible Materials: Strong acids, oxidizers, some metal powders
Hazardous Decomposition Products: Calcium oxide, tungsten trioxide upon strong heating
Hazardous Polymerization: Will not occur

Toxicological Information

Acute Toxicity: Data from animal studies indicate low toxicity. Inhalation of fine dust can irritate nose, throat, lungs
Skin Corrosion/Irritation: Mild irritation possible from repeated or prolonged contact
Eye Damage/Irritation: Dust can cause eye irritation
Respiratory Sensitization: Not known, but dust can provoke symptoms in sensitive individuals
Mutagenicity/Carcinogenicity: No evidence in published studies linking calcium tungstate to genetic or cancer risks
Chronic Effects: Prolonged repeated exposure to dust may cause lung irritation or mild pneumoconiosis in rare cases
Routes of Entry: Inhalation, skin, eyes, ingestion

Ecological Information

Aquatic Toxicity: Practically insoluble, limited immediate hazard, but releases tungstate ions in acidic conditions. High concentrations may be toxic to some aquatic organisms
Persistence and Degradability: Persistent in soils and sediments. Breakdown only in strong acid
Bioaccumulation Potential: Low, as calcium tungstate is poorly absorbed by organisms
Mobility in Soil: Immobile in neutral or alkaline soils, more mobile in acidic soils due to dissolution
Environmental Concerns: Avoid uncontrolled release into watercourses or drains

Disposal Considerations

Waste Treatment Methods: Dispose as nonhazardous solid waste in accordance with local, state, and federal regulations if uncontaminated
Contaminated Packaging: Wash and reuse containers if possible or incinerate/landfill as per regulatory guidelines
Special Precautions: Never discharge to sewage or water bodies.
Disposal Containers: Use containers designed for toxic heavy metal wastes for large volumes

Transport Information

UN Number: Not regulated for transport
Proper Shipping Name: Calcium Tungstate
Transport Hazard Class: Not classified as hazardous
Packing Group: Not assigned
Environmental Hazards: Not regarded as maritime pollutant or dangerous to air transport
Special Precautions: Prevent dust generation, secure packaging to avoid breakage in transit

Regulatory Information

OSHA Regulation: Not specifically listed as a hazardous material
TSCA Inventory: Listed
SARA Title III Sections 311/312: Classified for chronic health hazard due to dust
California Proposition 65: Not listed
Europe (REACH): Registered, no special hazard labeling
Canadian WHMIS: Not controlled
Labeling: Standard chemical labeling; warning against creating dust
Other National Regulations: Additional requirements may exist depending on local jurisdiction, especially regarding waste and worker exposure