Ingredient Dictionary

GUAIACOL

Guaiacol is a monomethoxybenzene that consists of phenol with a methoxy substituent at the ortho position.

Definition

Guaiacol is a monomethoxybenzene that consists of phenol with a methoxy substituent at the ortho position. It has a role as a disinfectant, a plant metabolite, an expectorant and an EC 1.1.1.25 (shikimate dehydrogenase) inhibitor. It is functionally related to a catechol.

Source: PubChem

US FDA substance register · UNII 6JKA7MAH9C · registered name Guaiacol · single chemical substance

Source: US FDA Unique Ingredient Identifier (UNII)

Cosmetic roles

Gives the product a scentPERFUMING

Safety & regulatory references

Not classified under Korea’s toxic-substance GHS list · existing chemical substance

Source: Korea toxic substances GHS register (NIER)

More data — names, identifiers, properties, test records, literature

Names & identifiers

GUAIACOLINCIPhenol, 2-methoxy-Synonym

CAS No.chemical registry number: 90-05-1
EC No.EU chemical inventory number: 201-964-7
DTXSIDUS EPA chemical ID: DTXSID0023113
DTXCIDUS EPA compound ID: DTXCID003113

IUPAC: 2-Methoxyphenol
Molecular formula: C7H8O2
Molecular weight: 124.139 g/mol

Measured properties

Appearance: O-methoxyphenol appears as colorless to amber crystals or liquid. Density (of solid) 1.129 g / cm3. Solidifies at 28 °C (82.4 °F), but may remain liquid for a long time even at a much lower temperature. Slightly water soluble. Soluble in aqueous sodium hydroxide. Used medicinally as an expectorant. Used, because of its anti-oxidant properties, as an anti-skinning agent for paints. · Other Solid
Odour: Aromatic odor · CHARACTERISTIC SWEET ODOR, SLIGHTLY PHENOLIC
Boiling point: 399 to 403 °F at 760 mmHg (NTP, 1992) · 205 °C
Melting point: SOLIDIFIES at 82.4 °F (NTP, 1992) · 32 °C
Solubility: Slightly soluble (NTP, 1992) · Soluble in carbon tetrachloride
Density: 1.13 at 70.5 °F (NTP, 1992) - Denser than water, will sink · 1.1287 g/cu cm at 21 °C
Stability: Darkens on exposure to air and light
Dissociation constant: pKa = 9.98
Colour: WHITE OR SLIGHTLY YELLOW CRYSTALLINE MASS OR COLORLESS TO YELLOWISH
Melting/freezing point: 28 ℃
Initial boiling point and range: 205 ℃(1013 hPa)
Flash point: 82 ℃
Vapour pressure: 0.1027584 ㎜Hg (0.137 hPa at 25 deg c)
Water solubility: 15000 ㎎/ℓ (20 deg c)
Relative density: 1.097 (25 deg c(relative density))
n-Octanol/water partition coefficient (Kow): 1.32
Auto-ignition temperature: 750 ℃
Molecular weight: 124.13

Values measured on the substance itself. The KOSHA data are a reference for writing and reviewing safety data sheets, not a specification for a commercial raw material.

Source: PubChem · KOSHA safety data sheets (Korea)

What products actually use it for

What the 8 products reported to the US EPA with this ingredient use it for. Products outside cosmetics are included, so the top few rows are its main uses.

Fragrance3
Intermediate2
Flavouring and nutrient2
No specific technical function1

Source: US EPA CompTox dashboard

Irritation and sensitisation studies

5 skin studies and 4 eye studies are on record.

Classed as moderate1

The study conclusions largely agree (100%). These tests are on the raw material itself; irritation at the amount in a finished product is a different question.

See all 9 studies

Not classified
Skin Irritation · Screening
Classification not possible
Skin Sensitization · Screening
Skin Irrit. 2
Skin Irritation · Authoritative
Category 6.3A (Category 2)
Skin Irritation · Read Across
Moderate or Mild Irritation
skin irritation: in vivo · Screening · OECD Guideline 404 (Acute Dermal Irritation / Corrosion) according to
Category 1
Eye Irritation · Screening
Eye Irrit. 2
Eye Irritation · Authoritative
Moderate or Mild Irritation
eye irritation: in vivo · Screening · OECD Guideline 405 (Acute Eye Irritation / Corrosion) according to
Category 6.4A (Category 2A)
Eye Irritation · Read Across