© 2026 Sinochem Nanjing Corporation,
All Right Reserved
Chemical Name: 1,3,5-Trimethylbenzene
Synonyms: Mesitylene
Chemical Formula: C9H12
Appearance: Colorless liquid with a distinct, sweet solvent odor
Common Uses: Ingredient in solvents, intermediates for dyes and resins, fuel additive
GHS Classification: Flammable liquid, Acute toxicity (inhalation/dermal/oral), Eye irritation, Skin irritation
Hazard Statements: Liquid and vapor ignite easily. Exposure can irritate airways. Has potential to impact organs with repeated or prolonged exposure.
Symptoms of Exposure: Dizziness, headache, nausea, skin and eye redness, respiratory discomfort
Pictograms: Flame, exclamation mark (as seen on chemical safety labels)
Main Ingredient: 1,3,5-Trimethylbenzene — typically above 95% by composition
CAS Number: 108-67-8
Other Components: Trace quantities of other alkyl benzenes may appear, depending on source; not generally a blend
Inhalation: Move outdoors, get fresh air. Watch for coughing, dizziness, or shortness of breath. If symptoms linger, seek a doctor.
Skin Contact: Rinse with running water. Remove contaminated clothes promptly. Seek medical attention for persistent irritation.
Eye Contact: Rinse with plenty of water for at least 15 minutes. Get medical attention if vision blurs or pain persists.
Ingestion: If swallowed, rinse mouth. Don’t induce vomiting. Seek immediate medical attention for large ingestion or symptoms like drowsiness or vomiting.
Suitable Extinguishing Media: Use foam, dry chemical, or carbon dioxide for small fires. Water spray can help cool nearby containers but may cause fire to spread if applied directly to spill.
Specific Hazards: Vapors can travel and flash back to source. Gives off toxic gases such as carbon monoxide when burning.
Protective Equipment for Firefighters: Wear full protective gear and self-contained breathing apparatus to avoid fumes.
Personal Precautions: Keep people not involved in cleanup away. Wear gloves, eye protection, and a properly-fitted respirator or mask if needed.
Spill Response: Contain spill with inert material like sand. Do not wash down drain. Collect in suitable, labeled container for safe disposal.
Environmental Protections: Prevent runoff into sewers or waterways. Not a friend to fish or aquatic critters.
Handling: Work in well-ventilated spaces. Avoid sources of sparks, open flames, and static discharge. Don’t smoke around it. Use the smallest amount possible.
Storage: Store in tightly closed containers, away from sunlight, incompatibles like strong oxidizers, and—importantly—sources of heat and ignition. Containers may pressurize and rupture if heated. Store at room temperature or cooler.
Exposure Limits: OSHA has not set a Permissible Exposure Limit. Some local limits or recommended values (like ACGIH) broadly suggest 25 ppm as a limit for similar compounds.
Personal Protective Equipment: Chemical-resistant gloves, goggles or face shield, flame-resistant lab coat. For vapor, use a respirator rated for organic vapors.
Ventilation: Use either local exhaust or general ventilation to keep vapor concentrations down.
Boiling Point: 164°C
Melting Point: -44°C
Flash Point: Approximately 48°C
Vapor Pressure: About 2 mm Hg at 25°C
Solubility: Negligible in water, mixes easily with most organic solvents
Odor: Sweet, aromatic scent
Density: About 0.864 g/mL at room temperature
Chemical Stability: Remains stable under typical storage and use conditions.
Incompatible Materials: Strong oxidizing agents, acids or bases. Avoid peroxides.
Hazardous Decomposition Products: Burns to carbon monoxide, carbon dioxide, and incompletely oxidized organics.
Hazardous Polymerization: Not a concern with 1,3,5-Trimethylbenzene.
Acute Effects: Exposure can lead to headaches, light-headedness, narcotic effects at high vapor levels, and irritation of skin or eyes.
Chronic Effects: Frequent exposure above recommended levels may impact liver, kidneys, or nervous system. Used for years as a solvent: folks working without good ventilation often complain of fatigue and memory issues.
Sensitization: Rare, but skin may become more sensitive upon repeat exposure.
Routes of Entry: Breathing vapor, skin contact, and accidental ingestion (usually rare outside industrial settings)
Aquatic Toxicity: Not friendly to aquatic life, even at low concentrations. Stretches of water near spills may see a sharp drop in fish and invertebrates.
Persistence and Degradability: Tends to linger in water and soil, breaks down slowly. Does not bioaccumulate much but toxins from breakdown can.
Mobility: Moderate ability to travel through soil, spreads if spilled.
Waste Disposal: Collect as hazardous chemical waste. High-heat incineration works best. Avoid pouring down drains or regular garbage.
Containers: Empty drums can be dangerous due to vapor. Triple rinse or send for professional disposal.
Regulatory Notes: Local and national rules may require documentation of disposal steps; check with environmental and waste authorities.
DOT Classification: Flammable liquid, UN No. 3295
Packing Group: III
Labeling: Marked as flammable for road, rail, sea, and air shipping. Secure containers tightly.
Special Cautions: Keep away from food and feed during transport. Avoid tossing or bumping drums around.
Occupational Safety: Covered by federal workplace safety laws, chemical right-to-know standards, and general industry safety rules.
Environmental Release: Reporting may be mandatory under spill or release laws. Not considered a greenhouse gas but regulated for water and air emissions in industrial settings.
Workplace Labelling: Must carry hazard pictograms and warning phrases under GHS. Training required if you handle, store, or dispose of it as part of your work.
