Material Safety Data Sheet: Ammonium Paratungstate

1. Identification

Product Name: Ammonium Paratungstate
Synonyms: Ammonium tungstate, Tungstic acid, ammonium salt
Chemical Formula: (NH₄)₁₀[H₂W₁₂O₄₂]·4H₂O
CAS Number: 11120-25-5
Recommended Use: Production of tungsten compounds, catalyst, ceramics, fireproofing, analytical chemistry
Supplier Information: Manufacturer’s details, physical address, emergency contact phone

2. Hazard Identification

Classification: Eye irritant, irritating to respiratory system and skin
Signal Word: Warning
Hazard Statements: Causes skin and serious eye irritation, may cause respiratory discomfort
Precautionary Advice: Avoid breathing dust, use protective gloves and eye protection, wash exposed skin after handling, avoid release to environment

3. Composition / Information on Ingredients

Chemical Name: Ammonium Paratungstate
Concentration: 98–100%
Molecular Weight: 3140.2 g/mol
Impurities: Trace amounts of moisture and minor tungstate contaminants

4. First Aid Measures

Inhalation: Move affected person to fresh air, offer oxygen if symptoms like shortness of breath persist, seek medical attention for ongoing respiratory effects
Skin Contact: Remove contaminated clothing, rinse skin thoroughly with soap and water, monitor for redness or discomfort, get medical attention if symptoms worsen
Eye Contact: Rinse with plenty of water for at least 15 minutes, hold eyelids open to allow thorough flushing, remove contact lenses if present and easy to do
Ingestion: Rinse mouth, drink water if conscious, avoid inducing vomiting unless directed by medical personnel, seek medical help if unwell

5. Fire-Fighting Measures

Suitable Extinguishing Media: Water spray, dry chemical, foam, carbon dioxide
Specific Hazards: Non-combustible, but may release ammonia and oxides of nitrogen during decomposition
Protective Equipment: Full protective suit and self-contained breathing apparatus
Special Procedures: Cool exposed containers with water, avoid inhalation of dust or decomposition gases

6. Accidental Release Measures

Personal Protection: Use dust mask or respirator, chemical-resistant gloves, safety goggles
Spill Cleanup: Avoid creating dust, sweep or vacuum material and place in a labeled waste container, wash spill site with water after pickup
Environmental Protection: Prevent material and runoff from entering drains or surface water, contain spill to minimize environmental contamination

7. Handling and Storage

Handling: Work in well-ventilated locations, minimize dust creation, avoid contact with skin and eyes, do not eat or drink while handling chemical
Storage: Store in tightly closed container, dry and cool place, segregate from strong acids, food, feed, and incompatible materials, keep away from heat and combustion sources

8. Exposure Controls and Personal Protection

Exposure Limits: No occupational exposure limits established specifically, general tungsten compounds: 5 mg/m³ (as tungsten), OSHA/ACGIH
Engineering Controls: Local exhaust ventilation, enclosed process, dust extraction
Personal Protection: NIOSH-approved respirator for dust or mist, chemical-resistant gloves, protective goggles, long-sleeved protective clothing, access to eye wash and safety shower

9. Physical and Chemical Properties

Appearance: White granular or crystalline solid
Odor: Odorless
Solubility: Slightly soluble in cold water, more soluble in hot water
pH: Slightly basic
Melting Point: Decomposes before melting
Boiling Point: Not applicable
Density: Approximately 2.17 g/cm³
Vapor Pressure: Not volatile
Decomposition Temperature: Above 250°C with release of ammonia and oxides

10. Stability and Reactivity

Chemical Stability: Stable under normal temperatures and pressures
Incompatible Materials: Strong acids, alkalis, oxidizing agents
Hazardous Decomposition: Ammonia, tungsten oxides, nitrogen oxides
Reactivity: May react with acids to release toxic ammonia gas

11. Toxicological Information

Acute Effects: Eye irritation, skin irritation, inhalation of dust may cause respiratory discomfort
Chronic Effects: Prolonged or repeated exposure may lead to mild effects on lungs or kidneys, evidence from animal studies
Sensitization: Not known to cause allergic reactions
Carcinogenicity: Not classified as carcinogenic by IARC, NTP, or OSHA
LD50 (Oral, Rat): >2000 mg/kg (low toxicity)

12. Ecological Information

Environmental Toxicity: Harmful to aquatic organisms at higher concentrations, risk of bioaccumulation low
Persistence: Inorganic substance, limited biodegradation, may persist in soil and water
Mobility: Moderately mobile in water, may leach in soil under certain conditions
Bioaccumulation: Unlikely to bioaccumulate in aquatic life at low concentration

13. Disposal Considerations

Waste Disposal: Dispose chemical and any contaminated absorbents using an approved waste disposal contractor, follow local, regional, and national regulations
Container Disposal: Empty containers should be triply rinsed, marked, and sent to approved recycling or waste facilities
Precautions: Do not dispose material in drains, watercourses, or landfill not designated for hazardous chemical waste

14. Transport Information

UN Number: Not regulated for transport by United Nations recommendations
Transport Hazard Class: Not a hazardous material
Packing Group: Not assigned
Labeling: General chemical, no special labeling required
Special Precautions: Ship in sealed containers to limit spillage, avoid mechanical shock to package

15. Regulatory Information

TSCA (US): Listed
REACH (EU): Registered
OSHA Hazard: Irritant
DSL (Canada): Listed
SARA Title III: Not subject to reporting, not classified as Extremely Hazardous Substance
Hazard Symbols: Irritant
Label Elements: Complies with GHS standards
Other State Regulations: May appear on local chemical inventories or right-to-know lists based on jurisdiction