Material Safety Data Sheet: Potassium Sulfate
Identification
Product Name: Potassium Sulfate
Chemical Formula: K2SO4
CAS Number: 7778-80-5
EC Number: 231-915-5
Synonyms: Sulfate of potash, Dipotassium sulfate
Intended Use: Fertilizer, laboratory reagent, industrial applications
Manufacturer Information: Contact details for supplier, including address and emergency telephone
Hazard Identification
Classification: Not classified as hazardous according to GHS
Physical Hazards: Non-flammable, non-combustible, low reactivity under normal storage
Health Hazards: Dust can cause mild irritation to respiratory tract, eyes, or skin
Environmental Hazards: Large releases may alter soil and water nutrient balance, with downstream effects
Label Elements: No signal word or pictogram, but good practice to avoid generating dust
Other Information: Not explosive, not oxidizing, and not acutely toxic
Composition / Information on Ingredients
Chemical Name: Potassium Sulfate
Common Name: Potassium Sulfate
PURITY: >99%
Impurities: Trace amounts of chloride or magnesium depending on source
Molecular Weight: 174.26 g/mol
Component Breakdown: Potassium 44.82%, Sulfur 18.39% by weight
First Aid Measures
Inhalation: Move person to fresh air, offer water, monitor for symptoms like coughing or shortness of breath. Seek attention if symptoms persist.
Skin Contact: Wash affected area thoroughly with soap and water. Remove any contaminated clothing and launder before reuse.
Eye Contact: Rinse eyes gently with water for at least 15 minutes, making sure eyelids are open. Remove contact lenses if present.
Ingestion: Rinse mouth, drink water to dilute, do not induce vomiting; seek attention if large quantity ingested or symptoms occur.
Advice to Physician: Symptomatic treatment only, material not known to be systemically toxic.
Fire-Fighting Measures
Suitable Extinguishing Media: Use water spray, dry chemical, CO2, or foam if involved with fire
Hazardous Combustion Products: Produces potassium oxides and sulfur oxides under extreme fire conditions
Firefighter Protection: Wear full gear including self-contained breathing apparatus due to potential for irritating fumes
Specific Hazards: Does not burn, does not contribute fuel to fire, but may decompose with enough heat
Accidental Release Measures
Personal Precautions: Avoid breathing dust, ventilate area, use dust mask and safety goggles
Environmental Precautions: Prevent runoff into waterways or storm drains to avoid ecosystem imbalances
Cleanup Methods: Use broom or vacuum to collect, place in suitable container for disposal or reuse
Decontamination: Wash spill site with plenty of water to remove residues
Handling and Storage
Handling: Minimize generation of dust, use personal protection for large volumes, keep away from incompatible materials like strong acids
Storage: Store in cool, dry, well-ventilated area, sealed in original packaging or non-reactive containers
Preventive Measures: Keep out of reach of children, protect from moisture to avoid caking, avoid direct sunlight which can break down packaging
Exposure Controls and Personal Protection
Occupational Exposure Limits: No specific limits for potassium sulfate, but keep dust as low as feasible — OSHA Particulates Not Otherwise Regulated (PNOR) 15 mg/m³ (total), 5 mg/m³ (respirable)
Engineering Controls: Use process enclosures, local exhaust ventilation, or dust suppression where needed
Respiratory Protection: Use NIOSH-approved respirator in dust-heavy environments
Eye Protection: Use chemical safety goggles or face shield
Skin Protection: Wear protective gloves; barrier creams may reduce mild irritation risk
Hygiene Measures: Wash thoroughly after handling; avoid eating or drinking near work area
Physical and Chemical Properties
Appearance: White or colorless crystalline powder
Odor: Odorless
Melting Point: Approximately 1,069°C (1,956°F)
Solubility: Soluble in water (110 g/L at 20°C)
Boiling Point: Decomposes before boiling
Density: 2.66 g/cm³
pH (1% solution): 5.5 to 8.5
Vapor Pressure: Negligible
Other: Stable as a solid under ambient conditions, non-volatile
Stability and Reactivity
Chemical Stability: Stable under normal temperatures and storage conditions
Possibility of Hazardous Reactions: No dangerous polymerization
Materials to Avoid: Strong acids (generates H2SO4 and other irritating vapors), reducing agents
Hazardous Decomposition Products: Sulfur oxides, potassium oxide fumes upon thermal decomposition
Conditions to Avoid: Excess heat, moisture which may cause clumping or caking
Toxicological Information
Routes of Exposure: Inhalation, skin contact, eye contact, ingestion
Acute Oral Toxicity: LD50 (rat, oral): >6,600 mg/kg (low toxicity)
Acute Dermal Toxicity: Not expected to be harmful
Inhalation Toxicity: Dust may cause mild irritation
Skin Irritation: May cause mild redness or dryness in sensitive individuals
Eye Irritation: Temporary discomfort or redness if dust contacts eyes
Chronic Effects: No evidence of long-term health effects from repeated exposure at low levels
Sensitization: Not sensitizing
Mutagenicity, Carcinogenicity, Reproductive Toxicity: Not classified for these categories by authoritative agencies, not listed by IARC, NTP, or OSHA
Ecological Information
Environmental Fate: Dissolves in water, dissociates to potassium and sulfate ions
Aquatic Toxicity: Not acutely toxic to freshwater organisms at typical environmental concentrations
Soil Impact: High doses may disrupt soil chemistry, potentially reducing plant diversity if misapplied
Bioaccumulation Potential: Does not bioaccumulate
Mobility in Soil: Highly movable, leaches to groundwater at high application rates
Persistence and Degradability: Inorganic compound, not degradable by biological or chemical means in the traditional sense, persists as ions
Other Information: Excess potassium in water can promote algal blooms with downstream effects
Disposal Considerations
Waste Treatment: Dispose according to national and local environmental regulations. Product can be diluted and flushed to sewer with plenty of water if permitted, or landfilled
Containers: Empty packaging should be reused or recycled if possible; otherwise, treat as solid waste
Precautions: Avoid releasing large amounts directly into waterways; always consult local authorities for guidance, keep records of disposal as required by law
Reuse: Material with no contamination can often be reused in the intended application
Transport Information
UN Number: Not regulated as hazardous for transport
Proper Shipping Name: Potassium Sulfate
Transport Hazard Class: Not classified as dangerous goods
Packing Group: Not assigned
Marine Pollutant: Not listed
Special Precautions: Avoid packaging damage during transport; keep containers secure to avoid leaks or spills
Regulatory Information
Labeling Requirements: Not classified as hazardous, but workplace labeling of containers is best practice
TSCA Status: Listed in the United States Toxic Substances Control Act inventory
REACH Registration: Registered under European REACH regulations
Other International Inventories: Both Canada DSL/NDSL and Australia AICS list potassium sulfate
Worker Protection: Covered by general chemical safety regulations. Employers must provide access to SDS, follow occupational exposure limits, and ensure relevant PPE is used
Community Right-to-Know: Not subject to SARA Title III Section 313 reporting
Other Regulations: Meets fertilizer product purity standards in use across multiple jurisdictions
