Reported in EPA TSCA Inventory. EPA Genetic Toxicology Program.

OSHA PEL: TWA 5 mg/m³
ACGIH TLV: TWA 5 mg/m³

1. Introduction of 4-Methoxyphenol
4-Methoxyphenol is a pink crystals or white waxy solid.

2. Properties of 4-Methoxyphenol
XLogP3: 1.3
H-Bond Donor: 1
H-Bond Acceptor: 2 
EINECS: 205-769-8
Melting Point: 56 °C
Water Solubility: 40 g/L (25 °C)
Stability: Stable. Combustible. Incompatible with halogens, oxidizing agents.
Surface Tension: 38.6 dyne/cm
Density: 1.109 g/cm³
Flash Point: 120.8 °C
Enthalpy of Vaporization: 49.94 kJ/mol
Boiling Point: 243 °C at 760 mmHg
Vapour Pressure: 0.0211 mmHg at 25 °C
Product Categories: Liquid Crystal intermediates; Aromatic Ethers; Phenol&Thiophenol&Mercaptan; API intermediates; Biochemistry; Building Blocks for Liquid Crystals; Functional Materials; Phenols (Building Blocks for Liquid Crystals); Reagents for Oligosaccharide Synthesis

3. Toxicity of 4-Methoxyphenol

Organism	Test Type	Route	Reported Dose (Normalized Dose)	Effect	Source
mouse	LD50	intraperitoneal	250mg/kg (250mg/kg)		National Technical Information Service. Vol. AD691-490,
rat	LD50	oral	1600mg/kg (1600mg/kg)		Kodak Company Reports. Vol. 21MAY1971,

4. Safety Information of 4-Methoxyphenol
Poison by intraperitoneal route. A skin irritant. When heated to decomposition it emits acrid smoke and fumes. See also ETHERS.
Hazard Codes: Xn
Risk Statements: 22-36-43 
R22:Harmful if swallowed. 
R36:Irritating to eyes. 
R43:May cause sensitization by skin contact.
Safety Statements: 24/25-26-37/39-46 
S24/25:Avoid contact with skin and eyes. 
S26: In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. 
S37/39:Wear suitable gloves and eye/face protection. 
S46:If swallowed, seek medical advice immediately and show this container or label.
WGK Germany: 1
RTECS: SL7700000
HS Code: 29095090

5. Preparation of 4-Methoxyphenol
P-anisaldehyde (50 mmol) is dissolved in CH₂Cl₂(100mL) and 2-NO₂C₆H₄SeSeC₆H₄NO₂-2(2 mmol) and 30% H₂O₂ (13mL, 128 mmol) are added. The mixture is stirred magnetically at room temperature (water bath) for 30 minutes. Insoluble catalyst is removed by filtration and washed with CH₂C_l2 (20mL) and water (20mL). It can be reused after drying. To the filtrate and washings, water (100mL) is added, and the layers are separated after shaking. The organic layer is washed subsequently with 10% NaHSO₃ solution (100mL), 10% Na₂CO₃ solution (100mL), water (100mL) and dried over Na₂SO₄. 4-methoxyphenol is obtained by alkaline hydrolysis of the residue. Yield: 93%.

6. Use of 4-Methoxyphenol
Mequinol is a drug used in combination with the drug Tretinoin in the treatment of liver spots. And it is used alone as a topical drug for medical depigmentation. Mequinol is also used as an inhibitor and stabilizer in vinyl and acrylic monomers, acrylonitriles, and various polymers especially for finished products. In ethers, chlorinated hydrocarbons and ethyl cellulose it is used as a stabilizer to inhibit peroxide formation.