SkinWis
SkinWis Scientific

Skincare Ingredient

Sign in to save this ingredient

Save ingredients to your skin profile and we'll use them when you look up products — instantly flagging what's reactive, neutral, or works well for your skin.

Propylene Glycol

In Skincare: Is Propylene Glycol Safe? Comedogenic Rating & Side Effects

Comedogenicity (pore clogging)
1/5 — Very low risk
Safety (overall safety)
2/5 — Low risk
Irritancy (skin irritation)
3/5 — Moderate risk

Safety Information

Limited safety data available for long-term use in high concentrations; may increase skin penetration of other ingredients, requiring caution in formulations with potentially irritating actives.

Quick Insights

At a glance

  • 01

    Propylene glycol functions as a humectant, drawing moisture to the skin.

  • 02

    This ingredient can improve the penetration of active ingredients into the skin.

  • 03

    Propylene glycol helps stabilize cosmetic formulations by preventing melting in high heat and freezing in low temperatures.

  • 04

    With a long history of safe use, propylene glycol is found in thousands of personal care products.

  • 05

    Chemically known as 1,2-propanediol, propylene glycol is a common ingredient in cosmetics.

Key Benefits

What Propylene Glycol does for your skin

1 benefits
Hydration

Overview

Ingredient Profile

Propylene glycol is a synthetic humectant that draws moisture to the skin and can improve the absorption of other ingredients. It functions as a stabilizer in cosmetic formulations, helping to maintain product consistency across varying temperatures. Extensive safety assessments by organizations like the Cosmetic Ingredient Review Board have confirmed propylene glycol’s safe use in cosmetics at concentrations up to 73% in leave-on products, and higher concentrations in rinse-off formulations.
Classifications
Humectant
Solvent
Texture Enhancer

Data & Research

Scientific Facts

Propylene glycol is metabolized in the human body into lactic acid, a naturally occurring substance produced during muscle exercise. It’s also utilized in the creation of artificial smoke and fog for fire-fighting training and theatrical productions.

Common Uses

Formulation in Propylene Glycol

Propylene glycol acts as a humectant, meaning it attracts and absorbs water. This property makes it useful in moisturizers to help reduce flaking and restore skin suppleness. It is also used as a skin-conditioning agent, viscosity-decreasing agent, solvent, and fragrance ingredient. Data from the 2019 U.S. FDA’s Voluntary Cosmetic Registration Program (VCRP) indicates that propylene glycol is present in approximately 14,395 products.

Role of Propylene Glycol

Active Cosmetic Mechanisms

FRAGRANCE

Scent Provider

Adds pleasant scent to cosmetic products

SCIENTIFIC ANALYSIS

// Evidence: Fragrance ingredients provide aromatic appeal through essential oils, aroma chemicals, and natural extracts. These volatile compounds interact with olfactory receptors creating scent perception. Fragrance design considers top notes (high volatility), middle notes (moderate volatility), and base notes (low volatility) for scent development over time. Must consider stability, allergen content, and regulatory compliance.

HUMECTANT

Moisture Magnet

Attracts and retains moisture in skin and hair

SCIENTIFIC ANALYSIS

// Evidence: Humectant ingredients draw water from the environment and deeper skin layers through hygroscopic properties. Common humectants include glycerin, propylene glycol, hyaluronic acid, urea, and alpha-hydroxy acids. These contain multiple hydroxyl groups or other hydrophilic functional groups that form hydrogen bonds with water molecules. Mechanism involves attracting water to the stratum corneum, reducing transepidermal water loss, and increasing skin hydration.

SKIN CONDITIONING - HUMECTANT

Hydration Booster

Draws moisture into skin for hydration

SCIENTIFIC ANALYSIS

// Evidence: Humectant-type skin conditioners attract and bind water to increase skin hydration. Key ingredients include glycerin, hyaluronic acid, sodium PCA, urea, and propylene glycol. These hygroscopic molecules form hydrogen bonds with water from dermis and environment, increasing water content in stratum corneum. The mechanism involves osmotic gradient creation and water binding through hydrophilic functional groups. Results in plumping effect and improved skin flexibility.

SKIN CONDITIONING - MISCELLANEOUS

General Skin Improver

Improves skin condition through various mechanisms

SCIENTIFIC ANALYSIS

// Evidence: This category includes skin conditioning ingredients working through mechanisms not classified as emollient, humectant, or occlusive. May include antioxidants providing protective conditioning, peptides supporting structural proteins, botanical extracts with various bioactive effects, or ingredients that improve skin condition through multiple simultaneous mechanisms. Provides diverse skin benefits that dont fit into other specific subcategories.

SOLVENT

Ingredient Dissolver

Dissolves other ingredients to create uniform formulations

SCIENTIFIC ANALYSIS

// Evidence: Solvents dissolve, dilute, or disperse other ingredients creating homogeneous solutions. Water is universal solvent for hydrophilic ingredients. Organic solvents include ethanol (dissolves fragrances, some actives), propylene glycol, and glycerin. Selection based on polarity matching between solvent and solute. Mechanism involves disrupting intermolecular forces in solute and surrounding with solvent molecules. Critical for maintaining ingredient solubility and product stability.

VISCOSITY CONTROLLING

Thickness Regulator

Adjusts product thickness and flow properties

SCIENTIFIC ANALYSIS

// Evidence: Viscosity controlling ingredients modify product flow characteristics through thickening or thinning. Thickeners include natural gums (xanthan, guar), synthetic polymers (carbomers, acrylates), and inorganic thickeners (silica, clays). Mechanism varies: polymer chain entanglement, hydrogen bonding networks, particle association, or swelling. Rheology modifiers create desired texture, prevent separation, control application properties, and affect sensory perception. Can produce Newtonian (constant viscosity) or non-Newtonian (shear-thinning, thixotropic) flow behavior.

Products

containing Propylene Glycol

10706 formulations
Acne Clearing Wash
Acne Clearing Wash
Peter Thomas Roth · cleanser
Queen Screen Lightweight Skinscreen SPF50+
Queen Screen Lightweight Skinscreen SPF50+
Ultra Violette · sunscreen
Fusskraft Red
Fusskraft Red
Gehwol · body-skincare

References

Scientific sources

[1]

CosmeticsInfo.org, Accessed April 2021, ePublication

[2]

Archives of Dermatological Research, November 2019, pages 337-352

[3]

Critical Reviews in Toxicology, April 2013, pages 363-390

[4]

International Journal of Toxicology, September-October 2012, pages 245S-260S

[5]

Skin Pharmacology and Applied Physiology, 2001, pages 72-81

Semantic Analysis

Similar Ingredients

Ingredients with similar chemical profiles and skincare properties.

Frequently Asked Questions

Propylene Glycol — common questions

What is Propylene Glycol in skincare?

Propylene glycol, also known as 1,2-propanediol, is a synthetic alcohol. It’s a viscous, colorless liquid with a faint, slightly sweet taste and is nearly odorless. Propylene glycol is commonly used in cosmetics and personal care products such as facial cleansers, moisturizers, bath soaps, shampoos, conditioners, deodorants, and shaving preparations. It’s also found in some food products (beer, baked goods, dairy, coffee, nuts, and soda) and as an inactive ingredient in certain medications. The

What does Propylene Glycol do? / Functions of Propylene Glycol?

Common functions: FRAGRANCE, HUMECTANT, SKIN CONDITIONING - HUMECTANT, SKIN CONDITIONING - MISCELLANEOUS, SOLVENT, VISCOSITY CONTROLLING.

What is the comedogenic rating of Propylene Glycol? / Is Propylene Glycol comedogenic?
1 1/5 — Very low risk

Propylene Glycol has a comedogenic rating of 1 out of 5. A rating of 1 means it is unlikely to clog pores.

Does it clog pores?
Unlikely to Clog Pores

Propylene Glycol is unlikely to clog pores (rating 1/5).

Is Propylene Glycol safe for skin?
2 2/5 — Low risk

Propylene Glycol has a safety rating of 2 out of 5. A rating of 2 means it is generally considered safe for most skin types. Note: Limited safety data available for long-term use in high concentrations; may increase skin penetration of other ingredients, requiring caution in formulations with potentially irritating actives.

Is Propylene Glycol good for sensitive skin?
3 3/5 — Moderate risk

Propylene Glycol has an irritancy rating of 3 out of 5. A rating of 3 means it may cause mild irritation for some.

What are the side effects of Propylene Glycol in skincare?

Known considerations: Limited safety data available for long-term use in high concentrations; may increase skin penetration of other ingredients, requiring caution in formulations with potentially irritating actives. Additional risks: skin irritation (irritancy rating 3/5).

)