Product Name: 4-Methoxyphenol
Synonyms: Mequinol, p-Methoxyphenol, Hydroquinone monomethyl ether
CAS Number: 150-76-5
Recommended Uses: Laboratory chemicals, antioxidants in various industrial applications, polymer inhibitor, pharmaceutical intermediate
Manufacturer Information: Includes complete manufacturer contact address, emergency telephone number, and technical support resources usually found on the latest distributor label
Product Code: Found on the container or invoice for order identification
Emergency Overview: White or off-white crystalline powder, faint aromatic odor, irritant
Hazard Classification (GHS): Acute toxicity (oral, category 4), skin irritation (category 2), eye irritation (category 2A), skin sensitization (category 1)
Signal Word: Warning
Hazard Statements: Harmful if swallowed, causes skin irritation, causes serious eye irritation, may cause an allergic skin reaction
Pictogram(s): Exclamation mark
Routes of Exposure: Inhalation, skin, eye, ingestion
Precautionary Statements: Wash hands after handling, avoid breathing dust, wear gloves, protective clothing, and eye protection
Chemical Name: 4-Methoxyphenol
Chemical Formula: C7H8O2
Molecular Weight: 124.14 g/mol
Concentration: ≥99% (technical or laboratory grade)
Impurities: Trace amounts of related phenolic compounds and moisture, typically <1%
Other Ingredients: No additional ingredients of concern noted in standard formulations
Inhalation: Move individual to fresh air, monitor for respiratory trouble, seek immediate medical advice if symptoms persist or worsen
Skin Contact: Immediately wash skin with plenty of water, remove contaminated clothing, use mild soap if available, seek medical attention for irritation or persistent redness
Eye Contact: Rinse eyes gently with water for at least 15 minutes, remove contact lenses if present and easy, keep eyelids apart, consult an ophthalmologist
Ingestion: Rinse mouth thoroughly, do not induce vomiting unless directed by medical professionals, seek prompt medical assistance, monitor for nausea or other symptoms
Important Symptoms and Effects: Dermal sensitization, skin irritation, redness, itching, gastrointestinal discomfort if ingested, possible breathing difficulties on inhalation
Indication of Immediate Medical Attention: Severe or ongoing symptoms after ingestion, inhalation of large amounts, or exposure of large skin areas
Suitable Extinguishing Media: Water spray, foam, dry chemical, or carbon dioxide
Unsuitable Extinguishing Media: Direct or strong water jets can spread the hazard
Specific Hazards: Toxic vapors such as carbon monoxide and carbon dioxide from combustion
Protective Equipment for Firefighters: Self-contained breathing apparatus, full protective chemical-resistant suit, secure isolated area and ventilate
Firefighting Instructions: Approach from windward side, contain runoff water, cool containers with water spray if exposed to fire
Decomposition Products: Carbon monoxide, carbon dioxide, and potentially phenolic compounds
Personal Precautions: Use personal protective equipment including gloves, goggles, and dust mask, ensure adequate ventilation, keep unnecessary people away
Environmental Precautions: Prevent entry into sewers, waterways, and soil, notify authorities if major amounts escape, minimize dust formation
Cleanup Methods: Sweep or scoop spilled material into suitable dry containers, avoid generation of airborne dust, dispose of in accord with local regulations, wash spill area with water after removal
Emergency Procedures: Isolate hazard area, ventilate space, increase airflow to mitigate dust, store cleaned material for permitted disposal or reprocessing
Handling: Avoid contact with skin, eyes, and clothing, use in well-ventilated environments, open containers gently to minimize dust, use dust extraction systems where needed, do not breathe dust or fumes
Storage: Store in tightly-closed containers, keep in cool, dry, ventilated area away from heat or sources of ignition, segregate from strong oxidizers and acids, keep away from food and drink, store in original packaging or compatible containers
Incompatible Materials: Strong oxidizing agents, strong acids, some metal salts
Specific Storage Recommendations: Clearly label containers, lock storage cabinets if required for controlled materials, avoid prolonged exposure to light and heat
Occupational Exposure Limit Values: No established OSHA or ACGIH exposure limits for 4-Methoxyphenol; internal company limits may apply, often recommend keeping time-weighted exposures as low as possible
Appropriate Engineering Controls: Provide local exhaust ventilation at points of dust generation, maintain general ventilation, install eye wash stations and showers
Personal Protective Equipment: Nitrile or neoprene gloves, chemical splash goggles, long-sleeved protective clothing, dust mask or organic vapor respirator as needed, avoid open-toe shoes, wash hands thoroughly after use
Environmental Exposure Controls: Take steps to avoid environmental contamination, use closed systems for large processes
Appearance: White to off-white crystalline solid, sometimes fine needles or granules
Odor: Mild aromatic or phenolic odor
Odor Threshold: Not determined
pH: Slightly acidic in aqueous solution
Melting Point: 52 – 56°C
Boiling Point: 243°C at 760 mmHg
Flash Point: 153°C
Evaporation Rate: Not applicable at ambient conditions
Flammability: Dust or fine powder may form flammable mixture with air
Vapor Pressure: 0.03 mmHg at 25°C
Vapor Density: 4.28 (air = 1)
Solubility: Low in cold water, good in organic solvents like alcohol, ether, chloroform
Partition Coefficient: log Kow ≈ 1.3
Auto-Ignition Temperature: 525°C
Decomposition Temperature: Not precisely documented, but above melting point material may decompose
Viscosity: Not relevant (solid at room temperature)
Chemical Stability: Stable under recommended storage and handling conditions
Reactivity: Mildly reactive with strong oxidizers and acids, can undergo slow air oxidation, especially in presence of light
Hazardous Reactions: Contact with strong oxidizing agents may lead to rapid exothermic reactions
Conditions to Avoid: Heat, moisture, direct sunlight, open flames
Incompatible Materials: Oxidizers like peroxides, nitric acid, halogens
Hazardous Decomposition Products: Phenols, carbon monoxide, carbon dioxide, traces of methylated aromatic compounds
Acute Toxicity: Oral LD50 (rat) ranges from 1200 to 1300 mg/kg; moderate toxicity; acute exposure can cause headaches, dizziness, or gastrointestinal discomfort
Skin Contact: May cause irritation, possible allergic reactions on repeated exposure
Eye Contact: Irritation, redness, watering, possible conjunctival damage if prolonged exposure
Inhalation: Irritation of respiratory tract, coughing, sneezing
Chronic Effects: Prolonged or repeated exposure may result in contact dermatitis or skin sensitization
Carcinogenicity: Not considered carcinogenic based on available data; not listed by IARC, NTP, OSHA
Mutagenicity: No reliable evidence of mutagenicity
Other Information: People with existing skin or respiratory conditions may be more susceptible to effects; always consult current literature for updated toxicology
Ecotoxicity: Toxic to aquatic life; acute LC50 for fish (96 hours) is 10-20 mg/L in some studies
Persistence and Degradability: Readily biodegradable under aerobic conditions; breakdown can lead to less toxic products, but still should be managed responsibly
Bioaccumulative Potential: Low bioaccumulation expected (log Kow ≈ 1.3)
Mobility in Soil: Moderate, potential for leaching through soil but subject to degradation
Other Adverse Effects: Large releases may impact stream or pond ecology, so avoid direct environmental discharge
Waste Disposal Methods: Dispose of excess or waste product in accordance with local, state, and federal regulations; use licensed hazardous waste disposal contractor
Packaging Disposal: Use proper containers for residue and rinse solutions, label as hazardous waste, recycle packaging where regulations permit and decontaminate where possible
Special Disposal Precautions: Avoid contamination of water sources and soil, do not flush into drains, consult authorities regarding chemical and container disposal if unsure
UN Number: 2811 (Toxic solid, organic, n.o.s. — varies by carrier and regulatory body)
Transport Hazard Class: 6.1 (Toxic substances)
Packing Group: III
Label(s) Required: Toxic, as defined by international regulations
Environmental Hazards: Marine pollutant, depending on volume and form
Special Transport Precautions: Secure container seals, handle in dry, ventilated compartments, keep separate from food and oxidizing agents
Regulations Apply: Compliant with DOT, IATA, IMDG, and ADR for chemical substances in this classification
U.S. TSCA: Listed on the Toxic Substances Control Act Inventory
EU REACH: Registered, check registration number with supplier
OSHA Hazard: Classified as hazardous by U.S. OSHA; hazard communication standard applies for workplace labeling and SDS
WHMIS (Canada): Classified as toxic and irritant; workplace labeling required
Other International: Not subject to major export restrictions, but must comply with chemical safety management laws under GHS in most countries
Other Notations: Regulatory compliance may require risk management measures, periodic safety training for workers, safety audits, and incident reporting according to jurisdictional rules
