Material Safety Data Sheet (MSDS) for Ammonium Heptamolybdate

Identification

Product Name: Ammonium Heptamolybdate
Synonyms: Ammonium molybdate tetrahydrate, Molybdic acid (ammonium salt), Ammonium paramolybdate
Chemical Formula: (NH₄)₆Mo₇O₂₄·4H₂O
CAS Number: 12054-85-2
Recommended Use: Laboratory reagent, pigment production, fertilizer additive, metal finishing
Supplier Information: Name, address, and phone number of the supplier or manufacturer
Emergency Phone: Emergency contact number for quick response

Hazard Identification

GHS Classification: Acute toxicity (oral, inhalation), Eye irritation, Skin irritation
Label Elements: Pictogram of exclamation mark, Signal word: Warning
Hazard Statements: May cause respiratory, skin, and eye irritation; Harmful if swallowed or inhaled; Possible environmental effects in aquatic systems
Precautionary Statements: Avoid breathing dust; Wear protective gloves, clothing, and eye protection; Wash hands thoroughly after handling; Do not eat or drink while working with the product
Routes of Exposure: Inhalation, ingestion, skin, and eye contact

Composition / Information on Ingredients

Chemical Name: Ammonium Heptamolybdate Tetrahydrate
Concentration: Typically above 99%
Impurities: Trace levels of molybdenum trioxide, ammonium chloride, water of crystallization
Molecular Weight: 1235.86 g/mol
Component Information: No hazardous impurities present at concentrations requiring disclosure under current regulations

First Aid Measures

Inhalation: Move person to fresh air immediately; provide oxygen if breathing becomes difficult; seek medical attention for persistent symptoms
Skin Contact: Remove contaminated clothing; wash affected area with plenty of water and soap; consult a physician if irritation continues
Eye Contact: Rinse eyes promptly with water for at least 15 minutes, keeping eyelids open; remove contact lenses if present; seek medical advice for pain or persistent redness
Ingestion: Rinse mouth thoroughly with water; do not induce vomiting; call a doctor or poison center for advice; never give anything by mouth to an unconscious person
Most Important Symptoms and Effects: Irritation to mucous membranes, coughing, shortness of breath, skin rash, eye discomfort

Fire-Fighting Measures

Suitable Extinguishing Media: Water spray, dry chemical, carbon dioxide, foam
Specific Hazards Arising: May emit toxic fumes of molybdenum oxides and nitrogen oxides under fire conditions
Special Protective Equipment: Firefighters should wear self-contained breathing apparatus and full protective gear
Advice for Firefighters: Use water spray to cool containers; avoid inhaling fumes; evacuate area in case of large fire
Explosion Data: Product itself does not present an explosion hazard under typical conditions; use caution in presence of combustible materials

Accidental Release Measures

Personal Precautions: Wear recommended personal protective equipment; avoid generating dust; ventilate area thoroughly
Environmental Precautions: Prevent product from entering soil, waterways, or drains; inform relevant authorities if significant spill occurs
Cleanup Methods: Sweep up spilled material without creating dust; transfer to clearly labeled container for disposal; wash spill site with water after material pickup
Additional Advice: Dispose of according to national and local regulations; avoid contamination of food and feed supplies

Handling and Storage

Handling: Use only in well-ventilated areas; avoid contact with eyes, skin, and clothing; keep container tightly sealed when not in use
Storage Conditions: Store in original packaging, cool, dry, well-ventilated area; keep away from acids, oxidizing agents, moisture, and combustible materials; avoid temperatures above 40°C
Incompatible Materials: Strong acids, reducing agents, alkalis
Storage Class: Store with inorganic chemicals; separate from foodstuffs and incompatible substances

Exposure Controls and Personal Protection

Occupational Exposure Limits: Molybdenum compounds (as Mo): OSHA PEL = 5 mg/m³ (soluble compounds), ACGIH TLV = 0.5 mg/m³ (respirable fraction)
Engineering Controls: Use local exhaust ventilation or other engineering controls to keep airborne levels below recommended exposure limits
Personal Protective Equipment: Safety glasses or goggles, chemical-resistant gloves, lab coat or apron; suitable respiratory protection for dust or powder work
Hygiene Measures: Wash hands after handling; do not eat, drink or smoke in area of use; remove contaminated clothing immediately

Physical and Chemical Properties

Appearance: White to faintly green, crystalline powder
Odor: Odorless
Melting Point: Not available (decomposes before melting)
Boiling Point: Not applicable
Solubility: Highly soluble in water, insoluble in ethanol or ether
pH (1% solution): Around 5.5 - 6.5
Density: 2.5 g/cm³
Vapor Pressure: Not relevant at standard conditions
Flammability: Non-flammable under recommended conditions of use
Decomposition Temperature: Releases ammonia, nitrogen oxides, and molybdenum oxides above 190°C
Partition Coefficient: No data available

Stability and Reactivity

Chemical Stability: Stable under normal storage and handling conditions
Possibility of Hazardous Reactions: Reacts with strong acids producing molybdic acid and ammonia, can react with reducing agents
Conditions to Avoid: Moisture, heat, incompatibles
Incompatible Materials: Acids, reducing agents, alkalis
Hazardous Decomposition Products: Nitrogen oxides, molybdenum oxides, ammonia gases if heated strongly or under fire conditions

Toxicological Information

Acute Toxicity: LD₅₀ (oral, rat): approximately 333 mg/kg; ingestion may cause gastrointestinal irritation, nausea, vomiting, diarrhea
Inhalation: Breathing dust can irritate respiratory tract; may cause coughing, sore throat, and shortness of breath
Skin Contact: May cause mild to moderate irritation on prolonged or repeated contact
Eye Contact: Dust particles can cause redness, tearing, discomfort
Chronic Effects: Frequent long-term exposure may impact liver and kidney function; possible systemic molybdenum toxicity
Carcinogenicity: Not classified as carcinogenic by IARC, NTP, OSHA
Mutagenicity: No reliable data available
Other Toxicity Data: Contact with ammonium salts may aggravate symptoms in individuals with pre-existing skin, respiratory, or kidney conditions

Ecological Information

Ecotoxicity: Toxic to aquatic organisms at high concentrations; LC₅₀ for fish: ranges from 175-1000 mg/L (96hr, species-dependent)
Persistence and Degradability: Not rapidly biodegradable; dissociates to ammonium and molybdate ions in water
Bioaccumulation Potential: Low potential for bioaccumulation in aquatic life
Mobility in Soil: Soluble; possible risk of groundwater contamination in case of high-volume spill
Other Adverse Effects: Excess molybdenum can disrupt nitrogen cycling in soil and water

Disposal Considerations

Waste Disposal Methods: Treat as hazardous waste; comply with local, regional, national, and international regulations; do not allow to enter the environment unprocessed
Product Disposal: Collect in appropriate containers for disposal at licensed chemical waste facility
Packaging Disposal: Rinse containers thoroughly before disposal or recycling; dispose of packaging in accordance with regulations
Contaminated Materials: Treat rinsate and contaminated items as chemical waste

Transport Information

UN Number: Not assigned for normal transport quantities
UN Proper Shipping Name: Not regulated as dangerous goods
Transport Hazard Class(es): Not classified
Packing Group: Not assigned
Environmental Hazards: Prevent release into environment during transport
Special Precautions for User: Keep containers tightly closed and upright; use appropriate transport packaging to prevent damage or spills

Regulatory Information

OSHA: Listed as hazardous due to toxicity and potential irritant effect
TSCA: Listed in the U.S. Toxic Substances Control Act inventory
REACH: Registered in Europe for approved uses; safety assessment required for quantities exceeding thresholds
DSL/NDSL (Canada): Statement about listing under Canadian regulations
SARA Title III: Not subject to reporting requirements for extremely hazardous substances
Other International Regulations: Follows classification and labeling in line with GHS and country-specific laws; chemical inventory compliance in Australia (AICS), Japan (ENCS), South Korea (ECL), China (IECSC)