Product Name: 2,3,5-Trimethylhydroquinone
Synonyms: TMHQ, 2,3,5-Trimethyl-1,4-benzenediol
CAS Number: 700-13-0
Molecular Formula: C9H12O2
Molecular Weight: 152.19 g/mol
Recommended Use: Intermediate for Vitamin E synthesis, laboratory chemical
Supplier: Chemical laboratory or industrial supplier identified on container label
Contact Number: Refer to safety officer or manufacturer provided number on shipping documentation or product label
Emergency Phone: Refer to local emergency directory or product-specific emergency line, common in all chemical shipments
GHS Classification: Acute toxicity (Oral, Category 4), Skin irritation (Category 2), Eye irritation (Category 2A)
Pictogram: Exclamation mark
Signal Word: Warning
Hazard Statements: Harmful if swallowed. Causes skin irritation. Causes serious eye irritation.
Precautionary Statements: Wash face, hands, and exposed skin thoroughly after handling. Wear protective gloves, protective clothing, eye protection, and face protection. Avoid breathing dust and vapors.
Potential Health Effects: Ingestion may cause gastrointestinal discomfort or acute toxicity. Contact can lead to skin inflammation or eye burns. Individuals with underlying respiratory or dermatological conditions may experience more severe reactions.
Chemical Identity: 2,3,5-Trimethylhydroquinone
Concentration: >98% by weight
Impurities: Trace levels of other methylhydroquinones or unreacted starting material may be present under 2%
CAS Number: 700-13-0
EC Number: 211-844-1
Other Identifiers: No significant non-hazardous stabilizers or additives reported in common laboratory packaging
Inhalation: Move exposed person to fresh air immediately. Seek medical attention if breathing becomes difficult or symptoms persist. Loosen tight clothing and provide oxygen if trained staff are available.
Skin Contact: Remove contaminated clothing and rinse skin with plenty of water for at least 15 minutes. Use mild soap to ensure thorough removal. If irritation continues, seek professional medical advice. Discard contaminated clothing properly.
Eye Contact: Immediately flush eyes with lukewarm, gently flowing water for at least 20 minutes while holding eyelids open. Remove contact lenses if present and easy to do.
Ingestion: Rinse mouth thoroughly with water. Never give anything by mouth to an unconscious person. Do not induce vomiting unless advised by medical personnel. Seek medical help for further assessment and observation.
Most Important Symptoms: Skin redness, eye pain, irritation, digestive discomfort, coughing, or headache after inhalation of dust
Suitable Extinguishing Media: Dry chemical powder, carbon dioxide, foam, or water spray. Avoid direct streams of water that may spread chemical dust.
Specific Hazards: May emit toxic fumes of carbon monoxide or carbon dioxide under fire conditions. Dust may form explosible mixtures in air, especially when finely divided.
Special Protective Equipment: Firefighters require self-contained breathing apparatus and full protective gear to prevent inhalation or skin contact.
Advice for Firefighters: Approach from upwind, avoid inhalation of combustion products, and prevent runoff from entering sewers or waterways.
Unusual Fire/Explosion Hazards: Combustible solid, may ignite if exposed to high heat or flame. Dust accumulation increases risk of rapid combustion.
Personal Precautions: Evacuate unnecessary personnel from affected area. Wear protective gloves, eye protection, and appropriate respirator if dust forms.
Environmental Precautions: Prevent material from entering drains, waterways, or soil. Notify environmental authorities in case of major spill.
Methods for Cleaning Up: Carefully sweep up without creating dust. Place in suitable, labeled chemical waste containers for disposal. Clean affected area with water.
Reference to Other Sections: Refer to personal protection (Section 8) and disposal considerations when handling collected material.
Decontamination: Wash surface with water and mild detergent to remove residues after spill cleanup is complete.
Handling: Keep containers tightly closed and handle in well-ventilated areas. Treat as an industrial chemical. Avoid generating or breathing dust.
Hygiene Measures: Do not eat, drink, or smoke when using this product. Wash hands thoroughly after handling. Remove contaminated clothing before reentering communal areas.
Storage: Store in cool, dry, and well-ventilated place. Protect from light, moisture, and incompatible substances including strong oxidizers.
Incompatible Products: Strong acids, strong bases, oxidizing materials.
Specific Use(s): Managed under chemical control processes, reserved for laboratory or manufacturing environments.
Control Parameters: Occupational exposure limits not established for TMHQ. Take precautions to avoid skin and eye contact.
Engineering Controls: Work in fume hood or with local exhaust ventilation to minimize airborne dust or vapor.
Personal Protective Equipment: Wear safety glasses or chemical splash goggles. Use chemical-resistant gloves such as nitrile. Don a laboratory coat or other protective garment. If handling powder in large quantities or poorly ventilated spaces, use a dust respirator.
Environmental Controls: Prevent release to the environment by containing spills and collecting waste appropriately.
Emergency Eyewash and Shower: Maintain immediate access in all work areas where handling takes place.
Appearance: White to light-yellow crystalline solid
Odor: Faint aromatic odor
Odor Threshold: Data not available
pH: Not applicable (not supplied in aqueous solution)
Melting Point: 168-172°C
Boiling Point: Decomposes before boiling
Flash Point: Above 150°C (closed cup, estimated)
Flammability: Combustible solid
Vapor Pressure: Negligible at room temperature
Vapor Density: Not determined
Density: Approximately 1.16 g/cm³ at 20°C
Solubility: Slightly soluble in water, more soluble in polar organic solvents (ethanol, acetone)
Partition Coefficient (n-octanol/water): Not available
Autoignition Temperature: Not established
Decomposition Temperature: Above 200°C
Viscosity: Solid, not applicable
Chemical Stability: Stable under recommended storage and handling conditions.
Possibility of Hazardous Reactions: May react with strong oxidizing agents, acids, or bases, which could trigger decomposition.
Conditions to Avoid: Exposure to heat, sparks, open flames, and incompatible chemicals.
Incompatible Materials: Strong oxidizers, strong acids and bases, peroxides.
Hazardous Decomposition Products: Thermal decomposition may yield carbon oxides, methylated byproducts, and possible irritant fumes.
Polymerization: No known risk of hazardous polymerization reported
Acute Toxicity: Data suggests low- to moderate-toxicity by oral, dermal, and inhalation routes. LD50 (oral, rat): estimated 800-1700 mg/kg.
Skin Contact: May cause inflammation, redness, or dermatitis on repeated exposure.
Eye Contact: Causes severe irritation, redness, tearing, and discomfort.
Inhalation: Dust or vapors can initiate coughing, sore throat, or respiratory discomfort.
Chronic Exposure: Repeated or prolonged contact with skin might increase risk of dermatitis.
Carcinogenicity: No listings by IARC, NTP, or OSHA.
Mutagenicity: No significant mutagenic effects recorded in standard laboratory assay data.
Other Health Effects: Individuals with pre-existing allergies or chemical sensitivities may suffer aggravation of symptoms
Ecotoxicity: Degrades slowly in natural environments. Toxicity data on aquatic species shows moderate effects at elevated concentrations.
Persistence and Degradability: Not readily biodegradable but subject to slow breakdown in surface waters and soils.
Bioaccumulation Potential: Potential to bioaccumulate is considered low due to low solubility and high reactivity.
Mobility in Soil: Moderate mobility, volatility negligible. Material can migrate in water-logged soils over time.
Other Adverse Effects: Significant uncontrolled releases may depress oxygen levels in surface waters.
Preventative Measures: Keep chemical from direct release into drainage or natural water sources.
Product Disposal: Dispose of content in accordance with local, regional, and national regulations. Incineration by licensed chemical waste disposal contractor is recommended for bulk waste.
Contaminated Packaging: Triple rinse and offer containers for recycling or disposal through approved waste contractor.
Recommendations: Do not discharge to surface waters or sewers. Refer to safety data and regulatory authority for accepted methods.
Additional Notes: Separate hazardous wastes from organic/aqueous laboratory chemicals as per institutional policy.
UN Number: Not regulated under main international transport codes (ADR/RID/IMDG/IATA).
Proper Shipping Name: Not classified as hazardous for transport according to current standards.
Hazard Class: Not assigned
Packing Group: No assignment given current non-hazardous status
Marine Pollutant: No classification
Special Precautions: Pack to prevent dust formation and accidental release in transit. Comply with national transport requirements for chemicals.
EU Regulations: Not listed as a hazardous substance under REACH Annex XIV or SVHC. Safety Data Sheet required for supplied quantities under REACH.
US Regulations: Not present on TSCA Inventory as a restricted substance. No CERCLA, SARA, or EPCRA thresholds.
Canadian Regulations: Present on Domestic Substances List (DSL). Not scheduled on WHMIS for specific hazard; treat as controlled product.
Country-Specific Information: Users must confirm local environmental and workplace requirements due to periodic regulatory updates.
Other International Compliance: Conforms to standard labeling, packaging, and workplace safety directives enforced in OECD countries.
