Material Safety Data Sheet - Monopotassium Phosphate (MKP)

Identification

Product Name: Monopotassium Phosphate
Chemical Formula: KH₂PO₄
Synonyms: MKP, Potassium dihydrogen phosphate, Potassium phosphate monobasic
CAS Number: 7778-77-0
EC Number: 231-913-4
Recommended Use: Fertilizer, food additive, laboratory reagent
Manufacturer: Refer to supplied container label for manufacturer and emergency contact.

Hazard Identification

Classification: Not hazardous under GHS classification (2012 OSHA Hazard Communication Standard).
Physical Hazards: No significant risks from the product as supplied.
Health Hazards: May cause mild skin or eye irritation. Dust inhalation can cause throat and respiratory discomfort.
Environmental Hazards: Over-application or spills may contribute to water body nutrient loading.
Label Elements: Non-hazardous, but dust precaution notices recommended.
Signal Word: Not applicable.
Precautionary Phrases: Minimize dust generation, wash hands after use, avoid eye contact.

Composition / Information on Ingredients

Chemical: Monopotassium Phosphate
Concentration: ≥ 98%
Impurities: Typical grades contain water-insolubles below 0.1%, trace sodium, and chloride ions.
Other Ingredients: None significant
Molecular Weight: 136.09 g/mol

First Aid Measures

Inhalation: Move person to fresh air, keep comfortable, consult doctor if symptoms persist.
Skin Contact: Wash with plenty of soap and water. Take off contaminated clothing and wash before reuse.
Eye Contact: Rinse cautiously with water for several minutes. Remove contact lenses if present and easy to do. Seek medical advice if irritation continues.
Ingestion: Rinse mouth, drink small amounts of water. Get medical attention if you feel unwell or large quantities are swallowed.
Symptoms: Dust contact may cause redness, coughing, mild irritation. No chronic effects known in normal use.

Fire-Fighting Measures

Flammability: Not flammable.
Suitable Extinguishing Media: Use agents suitable for surrounding fire: water spray, CO₂, foam, dry chemical.
Specific Hazards: Decomposition in fire can produce toxic fumes of potassium oxides and phosphorus oxides.
Protective Equipment: Wear self-contained breathing apparatus and protective clothing.
Special Procedures: Move containers away from fire area if safe. Avoid runoff into waterways.

Accidental Release Measures

Personal Precautions: Wear dust mask, protective gloves, eye protection.
Environmental Precautions: Prevent entry into surface water, sewers, soil.
Spill Cleanup Methods: Sweep or vacuum up, place in suitable labeled container for disposal. Avoid generating dust.
Emergency Procedures: Isolate spill area, ventilate as required.

Handling and Storage

Safe Handling: Use with adequate ventilation. Avoid breathing dust or direct contact with skin and eyes.
Hygiene Practices: Wash thoroughly after handling. Do not eat, drink, or smoke while using.
Storage Conditions: Store in tightly closed container, in cool, dry, well-ventilated area. Keep away from incompatible materials like strong acids and bases.
Incompatibilities: Avoid mixing with strong oxidizers, acids, bases. Keep separated from food.

Exposure Controls and Personal Protection

Exposure Limits: No established OSHA/ACGIH limits for this substance.
Engineering Controls: Use general ventilation. For dusty operations, use local exhaust.
Respiratory Protection: Wear dust mask or respirator if dust generation is likely.
Skin Protection: Use suitable protective gloves, work clothing for prolonged or repeated handling.
Eye Protection: Safety glasses with side shields or chemical splash goggles.
Other Protective Equipment: Eyewash stations and washing facilities should be available in large handling areas.

Physical and Chemical Properties

Appearance: White crystalline powder; sometimes granular or fine.
Odor: Odorless.
pH (solution): 4.2 – 4.7 (1% solution, 25°C).
Melting Point/Freezing Point: Decomposes above 400°C.
Boiling Point: Not applicable.
Solubility: Soluble in water (230 g/L at 20°C).
Density: 2.34 g/cm³.
Vapor Pressure: Negligible.
Flash Point: Not flammable.
Partition Coefficient: Not determined.
Decomposition Products: Potassium and phosphorus oxides at high temperature.

Stability and Reactivity

Chemical Stability: Stable under normal conditions.
Reactivity: Reacts with strong acids or bases.
Incompatible Materials: Strong oxidizers, strong acids, strong alkalis.
Hazardous Decomposition Products: Phosphorus oxides and potassium oxides if heated to decomposition.
Polymerization: Will not occur.

Toxicological Information

Acute Toxicity: Low toxicity expected. Oral rat LD₅₀ reported above 5,000 mg/kg.
Skin Irritation: Mild irritation possible after contact.
Eye Irritation: Slight temporary discomfort can occur.
Respiratory Effects: Inhalation of dust may cause coughing, sneezing.
Chronic Effects: No known chronic toxicity through relevant exposure routes.
Carcinogenicity: Not listed by IARC, NTP, OSHA.
Sensitization: Not expected to cause sensitization.

Ecological Information

Aquatic Toxicity: No acute toxicity at typical environmental concentrations. Overuse may cause eutrophication.
Persistence: Inorganic salt; dissolves, disperses, or is assimilated by plants.
Bioaccumulation: Does not bioaccumulate.
Mobility: Mobile in soil systems. Possible leaching if overapplied.
Other Adverse Effects: Excess phosphorus can disrupt aquatic ecosystems if released in large quantities.

Disposal Considerations

Waste Treatment Methods: Dispose in accordance with local, regional, and national regulations.
Contaminated Packaging: Rinse thoroughly before recycling or disposal.
Recommendation: Land application as fertilizer is often permitted, given compliance with agricultural guidelines.
Do Not: Release to waterways or sewer drains.

Transport Information

UN Number: Not regulated.
Proper Shipping Name: Not subject to ADR/RID/IMDG/IATA.
Hazard Class: Not classified as dangerous goods.
Packaging Group: Not applicable.
Environmental Hazards: Not a marine pollutant.
Special Precautions: Keep dry during transport, use sealed and labeled packages.

Regulatory Information

OSHA: Not specifically regulated as a hazardous chemical.
TSCA: Listed.
DSL/NDSL (Canada): Listed.
EU REACH: Registered.
SARA Title III Section 313: Not reportable.
WHMIS (Canada): Not classified as hazardous.
Chemical Safety Assessment: Not required for this product under most regulations.