Product Name: Dihydric Phenol
Synonyms: Hydroquinone, Benzene-1,4-diol, Quinol
Chemical Formula: C6H6O2
Recommended Use: Used in photographic developers, antioxidants, polymer production, dyes, and reagents.
Supplier: Manufacturer name, address, phone number provided on official documentation.
Emergency Contact: Refer to local poison center or emergency response service number.
Classification: Acute Toxicity (Oral, Dermal), Eye Damage/Irritation, Skin Sensitization, Specific Target Organ Toxicity - Repeated Exposure
Signal Word: Danger
Hazard Statements: Harmful if swallowed. Causes serious eye irritation. May cause an allergic skin reaction. May cause organ damage through prolonged or repeated exposure. Toxic to aquatic life.
Pictograms: Skull and crossbones, exclamation mark, health hazard, environment
Precautionary Statements: Avoid breathing dust or vapor. Wear protective gloves and eye/face protection. Use only outdoors or in well-ventilated area. Wash exposed skin thoroughly after handling. Contain spills to avoid environmental impact.
Chemical Name: Hydroquinone
CAS Number: 123-31-9
Purity: Typically exceeds 99%
Impurities: Trace organics, water <0.5%
Inhalation: Move person to fresh air. Support breathing as needed, seek medical attention promptly.
Skin Contact: Remove contaminated clothing. Rinse skin immediately with plenty of water, gently wash with soap. Get medical advice for irritation or persistent symptoms.
Eye Contact: Rinse cautiously with water for several minutes. Remove contact lenses if present and easy to do. Get urgent medical attention.
Ingestion: Rinse mouth thoroughly (do not induce vomiting). Call a physician or poison center at once.
Most Important Symptoms: Burning sensation, cough, redness, blisters, abdominal pain, headache, possible allergic reaction.
Advice to Physician: Treat symptomatically, monitor respiratory and gastrointestinal distress, address possible methemoglobinemia.
Suitable Extinguishing Media: Water spray (fog), dry chemical, foam, carbon dioxide.
Unsuitable Media: Do not use direct stream of water; may spread fire.
Hazards: Combustion releases irritating and toxic fumes such as carbon oxides.
Protective Equipment: Wear self-contained breathing apparatus and full protective clothing.
Special Procedures: Contain runoff to prevent entry into sewers or waterways. Cool exposed containers with water spray.
Personal Precautions: Evacuate unnecessary personnel, ventilate area, avoid inhalation of dust and contact with skin/eyes. Wear recommended protective gear.
Environmental Precautions: Prevent further leakage/spillage if safe to do so. Do not let material enter drains, surface water, or soil.
Spill Cleanup: Scoop up bulk material without generating dust. Dampen small spills to avoid airborne dust. Place collected material in suitable containers for disposal. Dispose using licensed waste service.
Handling: Minimize dust generation. Avoid breathing vapors/dust. Prevent all unnecessary exposure. Use appropriate personal protection equipment. Keep out of reach of untrained individuals.
Storage: Store in tightly closed, labeled containers in a cool, dry, well-ventilated place away from heat, sparks, and incompatible materials like oxidizers, strong acids, or bases. Protect from moisture and direct sunlight. Avoid freezing. Regularly check for signs of container damage or corrosion.
Incompatibility: Strong oxidizing agents, alkalis, acids, iron, and metal salts.
Occupational Exposure Limits: OSHA PEL: 2 mg/m³ TWA; ACGIH TLV: 1 mg/m³ TWA.
Engineering Controls: Use local exhaust ventilation where dust or vapor formation is possible.
Respiratory Protection: Wear NIOSH-approved respirators in absence of adequate ventilation.
Hand Protection: Use chemical-resistant gloves (nitrile, neoprene, or butyl rubber).
Eye/Face Protection: Safety goggles and face shield recommended.
Skin Protection: Wear lab coat, apron, or protective suit.
Hygiene: Wash thoroughly after handling and before eating or drinking. Remove contaminated clothing before entering common areas.
Appearance: White crystalline solid
Odor: Faint aromatic
Melting Point: 172-174 °C
Boiling Point: 285-287 °C
Density: 1.32 g/cm³
Solubility: Soluble in water, ethanol, ether
Vapor Pressure: Negligible at room temperature
pH (1% sol): Slightly acidic
Flash Point: 165 °C (closed cup)
Auto-ignition Temperature: 515 °C
Partition Coefficient (log Kow): 0.59
Decomposition Temperature: >170 °C
Odor Threshold: Not established
Chemical Stability: Stable under normal temperatures and pressures, sensitive to light and air with discoloration risk.
Possibility of Hazardous Reactions: May react violently with strong oxidizers; dust can form explosive mixtures with air.
Incompatible Materials: Oxidizing agents, bases, iron, silver, metal oxides.
Decomposition Products: Produces carbon monoxide, carbon dioxide, potentially corrosive vapors.
Conditions to Avoid: Excessive heat, flame, spark, direct sunlight, moisture, mechanical shock or static electricity.
Routes of Entry: Inhalation, skin and eye contact, ingestion.
Acute Toxicity: Oral LD50 (rat): 320 mg/kg; Dermal LD50 (rabbit): >2000 mg/kg.
Irritation: Causes moderate to severe eye and skin irritation.
Sensitization: May cause allergic reaction in sensitive individuals.
Chronic Effects: Prolonged contact may lead to skin depigmentation, kidney and liver effects, potential blood disorders (methemoglobinemia).
Mutagenicity: Evidence in lab animals.
Carcinogenicity: Not classified as human carcinogen by IARC, NTP, OSHA.
Reproductive Toxicity: No significant data in humans.
Symptoms of Overexposure: Nausea, vomiting, headache, dizziness, confusion, cyanosis.
Ecotoxicity: Toxic to aquatic life with long-lasting effects. LC50 (fish, 96h): 0.044 mg/L.
Persistence and Degradability: Rapidly biodegradable under aerobic conditions; slower in anaerobic.
Bioaccumulation: Low potential, log Kow = 0.59.
Mobility in Soil: Moderate mobility; leaches easily in water.
Other Adverse Effects: Risk for oxygen depletion in waterways and potential for bioactivity in sediment fauna.
Waste Treatment Methods: Dispose of as hazardous waste according to local, regional, or national regulations.
Contaminated Packaging: Clean containers as per disposal laws before recycling or reuse.
Special Instructions: Do not discharge in surface water or sanitary sewers. Incineration under controlled conditions preferred. Consult licensed hazardous waste disposal professionals.
RCRA Status: Waste code: U197, classified as hazardous waste.
UN Number: 3077
UN Proper Shipping Name: Environmentally hazardous substance, solid, n.o.s. (contains Hydroquinone)
Transport Hazard Class: 9 (Miscellaneous hazardous materials)
Packing Group: III
Marine Pollutant: Yes
Special Precautions: Keep containers upright and secure. Avoid temperature extremes during transport. Report leaks, spills, or container damage immediately.
TSCA Status: Listed
SARA Section 302: Not listed
SARA Section 313: Subject to reporting requirements
CERCLA Hazardous Substance: Reportable Quantity: 100 pounds
California Proposition 65: Not listed
DSL (Canada): Listed
OSHA Hazard Communication: Meets criteria as hazardous chemical
International Inventories: Registered in EU (REACH), Australia (AICS), China (IECSC), Japan (ENCS), Philippines (PICCS), and Korea (KECL). Check country-specific lists for up-to-date status.
Label Elements: Conforms to GHS standards, includes hazard pictograms and standard risk/safety phrases.
