Material Safety Data Sheet: Hexadecanethiol
1. Identification
Product Name: Hexadecanethiol
Chemical Formula: C16H34S
CAS Number: 29150-68-7
Synonyms: 1-Hexadecanethiol, Cetyl mercaptan
Recommended Use: Surface treatments, chemical synthesis, corrosion inhibitors
Manufacturer Details: Refer to supplier’s label for local distributor or manufacturer address and contact information
Emergency Contact: Check label or country’s poison control number for chemical emergencies
2. Hazard Identification
Hazard Classification: Flammable liquid, Acute toxicity (oral, dermal, inhalation), Skin and eye irritant, Aquatic toxicity
Label Elements: Flammable, Acute Toxic, Hazardous to Aquatic Life
Signal Word: Danger
Hazard Statements: Causes skin and eye irritation, Toxic if swallowed or inhaled, Harmful to aquatic life with long-lasting effects, May ignite at elevated temperature
Precautionary Statements: Avoid breathing vapors, use protective gloves, prevent release into environment, keep away from open flame or heat sources
3. Composition / Information on Ingredients
Component: Hexadecanethiol
Concentration: ≥98%
Impurities: Trace amounts of homologous thiols, water
CAS Number: 29150-68-7
EC Number: 249-846-8
4. First Aid Measures
Inhalation: Move affected person to fresh air. Monitor for breathing difficulties. Call for immediate medical assistance if symptoms persist.
Skin Contact: Remove contaminated clothing. Rinse skin thoroughly with soap and water for at least 15 minutes. Seek medical help if skin irritation develops.
Eye Contact: Rinse eyes with plenty of clean water, occasionally lifting upper and lower lids for at least 15 minutes. Remove contact lenses if present. Seek eye specialist’s advice if discomfort continues.
Ingestion: Rinse mouth with water. Keep individual calm and do not induce vomiting. Get immediate medical attention. Call local poison control or emergency room. Never administer anything by mouth to an unconscious person.
Most Important Symptoms: Irritation, redness, coughing, nausea, headache, drowsiness, sore throat
5. Fire-Fighting Measures
Suitable Extinguishing Media: Carbon dioxide (CO2), dry chemical powder, alcohol-resistant foam, water spray to cool containers
Unsuitable Media: Direct water jets may spread burning material
Hazardous Combustion Products: Carbon oxides (CO2, CO), sulfur oxides, toxic fumes
Firefighter Protection: Full protective equipment, self-contained breathing apparatus (SCBA)
Fire Hazards: Vapors may travel and cause flashback. Containers may rupture at high temperatures.
6. Accidental Release Measures
Personal Precautions: Evacuate area, ventilate the space, wear appropriate protective equipment like gloves, goggles, respirators
Environmental Precautions: Prevent run-off to soil, drains, or waterways. Notify authorities if large quantities enter aquatic environments.
Methods for Containment: Contain spill using sand, earth, or vermiculite. Stop the source of leakage if this can be done safely.
Clean-Up Method: Absorb with inert materials, place in suitable disposable containers, seal tightly. Wash site of release thoroughly with detergent and water. Dispose compliance with local regulations.
7. Handling and Storage
Handling: Only use in well-ventilated spaces. Avoid direct contact with skin or eyes, avoid inhaling vapors. Keep away from ignition sources, sparks, or static discharge. Use proper grounding.
Storage: Store in cool, dry, and well-ventilated locations, away from incompatible substances such as oxidizers, acids, and alkalis. Keep containers tightly sealed and out of direct sunlight. Observe fire safety protocols during storage.
8. Exposure Controls and Personal Protection
Occupational Exposure Limits: No specific national limits assigned; general limit for thiols or organic compounds may apply
Engineering Controls: Use chemical fume hood, mechanical exhaust, ensure facility is equipped with eyewash and safety shower
Personal Protective Equipment: Chemical-resistant gloves (nitrile, butyl rubber), safety goggles or face shield, flame-resistant lab coat, proper footwear
Respiratory Protection: If ventilation inadequate, use an approved half- or full-face respirator with organic vapor cartridge
Hygiene Measures: Wash hands thoroughly after handling, avoid eating or drinking in work area, remove contaminated clothing promptly
9. Physical and Chemical Properties
Appearance: Clear to pale yellow oily liquid
Odor: Skunky, characteristic thiol odor
Odor Threshold: Detectable at very low concentrations
Melting Point: 39°C–41°C
Boiling Point: 330°C at atmospheric pressure
Flash Point: Approx. 154°C
Auto-ignition Temperature: 310°C
Explosive Limits: Not established for this compound
Vapor Pressure: Very low at 20°C
Density: 0.85 g/cm³ (20°C)
Solubility: Insoluble in water, miscible with organic solvents such as ethyl ether, chloroform
pH: Not applicable
Viscosity: Slightly viscous liquid at room temperature
Partition Coefficient (n-octanol/water): High (log Pow >6)
10. Stability and Reactivity
Chemical Stability: Remains stable under standard laboratory conditions in sealed packaging
Reactivity: Thiols may react with oxidizers, acids, alkalis
Conditions to Avoid: Excessive heat, flames, sparks, direct sunlight, storing with incompatible materials
Incompatible Materials: Strong acids, strong bases, strong oxidizers, reducing agents, halogens
Hazardous Decomposition Products: Sulfur oxides, hydrogen sulfide, carbon monoxide, carbon dioxide under fire or intense heat
Hazardous Polymerization: Not reported under normal use
11. Toxicological Information
Routes of Exposure: Inhalation, skin contact, eye contact, ingestion
Acute Toxicity: Oral LD50 (rat): 1,600 mg/kg
Skin Absorption: May produce mild to severe irritation, possible absorption with prolonged exposure
Inhalation: Vapors provoke respiratory tract irritation, headaches, dizziness, drowsiness, possible nausea
Eye Effects: Burning, redness, conjunctival swelling
Chronic Effects: Repeated or prolonged exposure may cause sensitization, dermatitis, possible liver or kidney damage
Carcinogenicity: Not classified as carcinogenic based on available data
Mutagenicity: No clear evidence from current studies
Reproductive Toxicity: Data insufficient to determine
12. Ecological Information
Aquatic Toxicity: Harmful to aquatic life with potential for long-term effects in rivers and lakes
Persistence and Degradability: Not readily biodegradable, may persist in soils and sediments
Bioaccumulative Potential: High potential for bioaccumulation in organisms due to hydrophobicity
Mobility in Soil: Low mobility in water; binds strongly to soil particles and organic matter
Other Environmental Information: Avoid contamination of the environment. Even small spills threaten aquatic species and quality of surface waters.
13. Disposal Considerations
Waste Treatment Methods: Collect contaminated materials and residues in tightly closed labeled containers
Disposal: Transport waste to chemical disposal plant approved for hazardous organic chemicals. Comply with local, national, and international regulations on hazardous waste disposal.
Contaminated Packaging: Empty containers must be triple-rinsed, rendered unusable, and disposed of in accordance with regulations.
Reuse/Recycling: Only consider if strictly permitted and safe, consult local authorities for advice on approved methods
14. Transport Information
UN Number: 3334
UN Proper Shipping Name: Aviation regulated liquid, n.o.s. (Hexadecanethiol)
Transport Hazard Class: Class 9 (Miscellaneous dangerous substances)
Packing Group: III
Environmental Hazards: Harmful to aquatic environment
Special Precautions for Transport: Secure containers tightly, prevent leaks, transport upright, avoid damage to packaging
Additional Shipping Information: Check local, air, sea, and rail transport requirements for country-specific rules or variations
15. Regulatory Information
US Regulations: Listed in TSCA inventory. SARA 313 reporting not required for this chemical. OSHA hazard communication applies.
EU Regulations: Reach registered substance. Hazard symbol: Xi (Irritant), N (Dangerous to the environment). Follows CLP/GHS classification.
Canada: DSL listed.
Labeling Requirements: Ensure all packaging displays appropriate hazard warning symbols, risk phrases, and precautionary statements in compliance with national regulation.
Other International: Confirm regulatory status in country of use due to regional differences in labeling and handling.
