Product Name: 4-(2-Hydroxyethyl)Piperazin-1-Ylethanesulphonic Acid
Synonyms: HEPES, N-(2-Hydroxyethyl)piperazine-N’-2-ethanesulfonic acid
CAS Number: 7365-45-9
Recommended Uses: Biological buffer, laboratory reagent, biochemical studies
Supplier Information: Manufacturer and distributor details with emergency contact number, address, and technical assistance line
Emergency Numbers: 24-hour access to poison response centres and local fire department or hazardous chemical team contact
Classification: May not meet the criteria for hazardous chemical under GHS, yet laboratory exposure can irritate eyes, skin, and respiratory system
Signal Word: Not classified as hazardous for most uses, yet treat with caution
Hazard Statements: Causes mild skin irritation, eye irritation, prolonged contact may aggravate conditions, avoid heavy inhalation or accidental ingestion
Precautionary Statements: Use appropriate personal protective equipment, avoid dust formation, wash thoroughly after handling, ensure sufficient ventilation
Label Elements: Pictograms not typically required, but facilities may apply “Exclamation Mark” symbol where regulation dictates
Health Hazards: Inhalation may cause respiratory tract irritation; skin or eye contact may cause redness or discomfort; ingestion in large amounts can upset digestive system
Environmental Hazards: Large releases could impact aquatic environments, chronic exposure effects not well characterized
Chemical Name: 4-(2-Hydroxyethyl)piperazin-1-ylethanesulphonic acid
Common Name: HEPES
Concentration: 98–100% pure substance commonly supplied as solid or buffered solution
Impurities and Additives: Minimal or absent under reputable suppliers, trace contaminants possible depending on source but typically less than 1%
Other Components: None relevant to safety classification; does not carry known hazardous contaminants at standard laboratory grade
Eye Contact: Flush eyes immediately with plenty of flowing water for at least 15 minutes, lifting eyelids occasionally, remove contact lenses if present, and continue rinsing, seek medical attention if irritation persists
Skin Contact: Wash thoroughly with soap and water, remove contaminated clothing, consult a physician for persistent symptoms or if rash develops, contaminated clothing should be laundered before reuse
Inhalation: Move person to area with fresh air, ensure airway remains unobstructed, provide artificial respiration or oxygen if breathing is difficult, medical attention is recommended for any ongoing respiratory irritation
Ingestion: Rinse mouth with water, do not induce vomiting unless directed by medical personnel, provide water to dilute residue in mouth, consult a physician or poison control centre in case of large accidental ingestion or symptoms such as nausea, vomiting, or abdominal cramps
Acute Symptoms: May include mild irritation to eyes, nose, or throat; rarely causes systemic symptoms
Suitable Extinguishing Media: Use water spray, dry chemical, carbon dioxide (CO2), or foam as appropriate for surrounding materials and fire type
Unsuitable Extinguishing Media: Avoid high-pressure water jets that might disperse solid powders and create airborne dust
Special Protective Equipment: Wear self-contained breathing apparatus (SCBA) and full protective gear in any situation involving fire or decomposition products
Specific Hazards: This material can yield toxic fumes under extreme heat, including nitrogen oxides, sulfur oxides, and carbon monoxide, follow local emergency protocols during response
Firefighting Instructions: Move containers from fire area if safe to do so, cool exposed containers with water spray, prevent water and runoff from entering drains or natural waterways
Personal Precautions: Evacuate personnel in immediate area not involved in cleanup, use dust mask or respirator, goggles, compatible gloves, and lab gown, avoid creating dust or breathing airborne particles, avoid skin and eye contact
Environmental Precautions: Prevent substance from entering watercourses, sewers, or confined spaces, contain spill using compatible absorbent materials and minimize dust generation
Spill Cleanup Methods: Sweep or scoop up spillage, place in suitable labeled waste container for disposal, wash area with large amounts of water to remove residue, ventilate area upon completion
Other Precautions: Decontaminate tools and equipment after cleanup, consult institutional safety team for large releases
Handling: Employ proper laboratory protocols, avoid unnecessary exposure, minimize dust generation during transfers, use in well-ventilated area, keep containers tightly closed, avoid eating, drinking, or smoking while handling the material
Storage Conditions: Store at room temperature or cooler in a tightly closed container, avoid excessive moisture, direct sunlight, and sources of ignition, segregate from incompatible substances including strong oxidizing agents and acids
Technical Measures: Provide access to eyewash stations and safety showers near storage and usage locations, label containers clearly, rotate stock using first-in, first-out method to maintain material stability
Occupational Exposure Limits: No specific regulatory occupational exposure limits established, yet general laboratory best practices recommend minimizing airborne concentrations
Engineering Controls: Ensure adequate laboratory ventilation, use chemical fume hood or local exhaust during procedures generating dust or aerosol, apply enclosure or isolation equipment as needed
Respiratory Protection: Use NIOSH/MSHA approved dust masks or respirators during times of potential dust formation or if ventilation is insufficient
Eye Protection: Chemical splash-resistant safety goggles
Skin Protection: Standard laboratory gloves and lab coat, higher protection such as chemical-resistant nitrile gloves for large-scale procedures, barrier cream for extra precaution
Hygiene Measures: Remove contaminated clothing, wash thoroughly after handling, maintain separation between work and eating areas
Appearance: White crystalline powder
Odor: Practically odorless
Odor Threshold: Data not available
pH: 5.0–6.0 (50 g/l at 20°C in water)
Melting Point/Freezing Point: Approximately 234–238°C with decomposition
Boiling Point/Range: Not applicable (decomposes before boiling)
Flash Point: Not applicable
Evaporation Rate: Not applicable
Flammability: Not flammable under normal conditions
Vapor Pressure: Not applicable
Vapor Density: Not applicable
Specific Gravity/Density: About 1.083 g/cm³ (water = 1)
Solubility: Highly soluble in water, practically insoluble in ethanol, ether, chloroform
Partition Coefficient (n-octanol/water): Not determined
Auto-ignition Temperature: Not known
Decomposition Temperature: Above 200°C
Viscosity: Not applicable
Chemical Stability: Stable under recommended storage and handling conditions, does not readily polymerize or degrade at room temperature away from moisture contamination
Conditions to Avoid: Excess heat, ignition sources, prolonged exposure to moist or humid environments, direct sunlight, strong acids or oxidizing agents
Incompatible Materials: Strong oxidizers, strong mineral acids, reactive halogens may initiate hazardous reactions
Decomposition Products: Under fire or extreme heat, may decompose to form hazardous gases including nitrogen oxides, sulfur oxides, carbon monoxide, carbon dioxide
Possibility of Hazardous Reactions: Does not pose a risk of dangerous polymerization or violent reaction under normal laboratory conditions
Likely Routes of Exposure: Skin and eye contact, inhalation of dust, accidental ingestion
Acute Toxicity: Oral, dermal, and inhalation toxicity generally considered low, LD50 (oral, rat) exceeds 4000 mg/kg, higher doses may cause gastrointestinal upset, nausea, or local irritation
Skin Irritation: Mild transient irritation possible on repeated or prolonged skin exposure
Eye Irritation: May cause redness, tearing, stinging if splashed directly in eyes
Respiratory Sensitization: Not known to cause respiratory sensitization, yet dust may cause mild upper airway irritation
Chronic Effects: No known chronic health effects reported with typical laboratory or industrial exposure levels
Carcinogenicity: Not listed as carcinogen by NTP, IARC, OSHA, or ACGIH
Mutagenicity: No data suggest mutagenic effects in laboratory species
Reproductive Toxicity: Not known to cause reproductive harm
Ecotoxicity: Low acute and chronic toxicity to aquatic life based on available studies, large quantities may impact water quality by altering pH or buffering capacity
Persistence and Degradability: Moderately persistent, slowly biodegradable under environmental conditions, not volatile
Bioaccumulative Potential: Not expected to bioaccumulate due to high water solubility and low partition coefficient
Mobility in Soil: Expected to have high mobility through soil in aqueous solution, may leach into groundwater if released in significant amounts
Other Effects: No known ozone depletion, global warming, or photochemical smog contributions
Waste Treatment Methods: Material should be collected for disposal as hazardous or chemical waste in accordance with institutional, local, regional, and national regulations
Disposal of Containers: Thoroughly rinse and deface labels before discarding in appropriate chemical waste container, avoid reuse of containers
Recommended Disposal Options: Incineration in licensed chemical incinerator, or as permitted by local waste handling authorities
Special Precautions: Prevent large-scale release to sewers or natural waterways, consult environmental health and safety officers before large-scale disposal activities
UN Number: Not regulated as a hazardous material for transport under UN, IMO, IATA, or DOT regulations
Proper Shipping Name: Not regulated; ship as laboratory chemical or scientific reagent, use original packaging with correct labeling
Transport Hazard Class: Not assigned
Packing Group: Not assigned
Environmental Hazards: None known for routine small shipments
Special Precautions for User: Maintain chemical container integrity, avoid generating dust during transport and handling, ship with compliance to institutional protocols
Transport in Bulk: Not applicable due to substance type and use
US Federal Regulations: Not specifically listed on SARA 302/304, SARA 311/312, or SARA 313; not listed as a hazardous air pollutant or priority pollutant
TSCA Status: Listed on United States TSCA Inventory
Canadian Regulations: DSL/NDSL listed (Canada Domestic Substances List)
EU Regulation: Not classified as dangerous under Regulation (EC) No. 1272/2008 (CLP), not subject to Special Restrictions (Annex XVII Reach)
OSHA: Not classified as hazardous chemical under US OSHA Hazard Communication Standard
Other International Listings: Complies with chemical inventory or notification requirements in Australia, China, Japan, Korea, New Zealand, and Philippines
Other Regulatory Notes: Product safety data sheet meets requirements set forth under GHS and applicable regional laws and guidelines, no known export controls or use restrictions at laboratory scales
