Ingredient Dictionary

PROPYLENE GLYCOL

Propane-1,2-diol is the simplest member of the class of propane-1,2-diols, consisting of propane in which a hydrogen at position 1 and a hydrogen at position 2 are substituted by hydroxy groups.

How much products actually contain

No product states its amount yet.

Of the products containing it, 767 list it before the 1% line and 745 after it (usually 1% or less).

Products using this ingredient

12 of 1,495 confirmed · likeliest to carry enough first · See all 1,495

Definition

Propane-1,2-diol is the simplest member of the class of propane-1,2-diols, consisting of propane in which a hydrogen at position 1 and a hydrogen at position 2 are substituted by hydroxy groups. A colourless, viscous, hygroscopic, low-melting (59C) and high-boiling (188C) liquid with low toxicity, it is used as a solvent, emulsifying agent, and antifreeze. It has a role as a protic solvent, an allergen, a mouse metabolite and a human xenobiotic metabolite. It is a glycol and a member of propane-1,2-diols.

Source: PubChem

US FDA substance register · UNII 6DC9Q167V3 · registered name Propylene Glycol · single chemical substance

Source: US FDA Unique Ingredient Identifier (UNII)

Propylene Glycol is the aliphatic alcohol that conforms generally to the formula

Cosmetic roles

Listed as a fragrance-composition material (not a claim that it adds scent)FRAGRANCEDraws moisture into the skinSKIN CONDITIONING - HUMECTANTSkin conditioning not covered aboveSKIN CONDITIONING - MISCELLANEOUSBase that dissolves other ingredientsSOLVENTDraws in and holds moistureHUMECTANTAdjusts thicknessVISCOSITY CONTROLLING

Safety & regulatory references

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

Source: Korea toxic substances GHS register (NIER)

Reviewed by CIR: Final Report on the Safety Assessment of Propylene Glycol and Polypropylene Glycols

Source: US Cosmetic Ingredient Review (CIR)

Reviewed by CIR: Safety Assessment of Propylene Glycol, Tripropylene Glycol and PPGs as Used in Cosmetics

Source: US Cosmetic Ingredient Review (CIR)

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

Official labels & definitions

JCIA labelling name ＰＧ: 本品は、次の化学式で表される二価アルコールである。

Source: JCIA labelling names (Japan)

Names & identifiers

PROPYLENE GLYCOLINCI프로필렌글라이콜Korean label name (MFDS standard)1,2-PropanediolSynonymＰＧJapanese labelling name

CAS No.chemical registry number: 57-55-6
EC No.EU chemical inventory number: 200-338-0
DTXSIDUS EPA chemical ID: DTXSID0021206
DTXCIDUS EPA compound ID: DTXCID901206

IUPAC: Propane-1,2-diol
Molecular formula: C3H8O2
Molecular weight: 76.095 g/mol

Measured properties

Appearance: Thick odorless colorless liquid. Mixes with water. (USCG, 1999) · Large Crystals, CBI, Liquid, Wet Solid, Other Solid
Odour: Practically odorless · odourless
Boiling point: 370.8 °F at 760 mmHg (NTP, 1992) · 187.6 °C
Melting point: -76 °F (NTP, 1992) · -60 °C
Solubility: greater than or equal to 100 mg/mL at 70 °F (NTP, 1992) · 1000000 mg/L (at 20 °C)
Density: 1.04 at 68 °F (USCG, 1999) - Denser than water, will sink · 1.0361 g/cu cm at 20 °C
Stability: At cool temperatures, propylene glycol is stable in a well-closed container, but at high temperatures, in the open, it tends to oxidize, giving rise to products such as propionaldehyde, lactic acid, pyruvic acid, and acetic acid. Propylene glycol is chemically stable when mixed with ethanol (95%), glycerin, or water, aqueous solutions may be sterilized by autoclaving.
Viscosity: 0.581 cP at 20 °C · 43.428 mPa S
Dissociation constant: 14.9 · pKa = 14.8 at 25 °C
Colour: colourless
pH: 6~8 (100 g/ℓ, 20℃)
Melting/freezing point: &amp, lt, ℃
Initial boiling point and range: 184 ℃
Flash point: 104 ℃
Evaporation rate: 0.01
Upper/lower flammability or explosive limits: 12.6 / 2.6 %
Vapour pressure: 20 ㎩ (25℃)
Water solubility: 100 % (20℃, pH: 7.1~7.8)
Vapour density: 1.0361 g/㎤ (20℃)
Relative density: 1.03
n-Octanol/water partition coefficient (Kow): 0.085 (Pow, 20.5℃)
Auto-ignition temperature: 400 ℃ (100.01~101.44 kPa)
Decomposition temperature: 403 ℃
Molecular weight: 76.09

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 1,166 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.

Solvent410
Solubility enhancer197
Processing aids not otherwise specified102
Humectant96
Fragrance72
Softener and conditioner51
Stabilizing agent41
No specific technical function35

38 other uses

Preservative21
Degradant/impurity (EPA)17
Viscosity modifier14
Diluent11
Coalescing agent10
Thickening agent9
Anti-freeze agent8
Wetting agent (non-aqueous)7
Surfactant (surface active agent)6
Monomers5
Cleaning agent4
Plasticizer4
Pigment4
Film former4
Biocide3
Soil amendments3
Intermediate3
Surface modifier3
Flavouring and nutrient2
Deodorizer2
Antioxidant2
Defoamer2
Absorbent2
Dye2
Filler1
Chemical reaction regulator1
Freeze-thaw additive1
Lubricating agent1
Adhesion/cohesion promoter1
Flow promoter1
Emulsifier1
Elasticizer1
Brightener1
Heat transferring agent1
Anti-caking agent1
Drier1
Hardener1
Pharmaceutical excipient (EPA)1

Source: US EPA CompTox dashboard

Irritation and sensitisation studies

1 skin studies and 0 eye studies are on record.

Classed as low1

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 1 studies

Studies Indicate No Significant Irritation
skin irritation: in vivo · Screening · OECD Guideline 404 (Acute Dermal Irritation / Corrosion) according to