Ingredient review

PEG-100 Lanolin

INCI: PEG-100 Lanolin

PEG-100 Lanolin is a water-friendly version of lanolin that softens skin and helps blend oil and water, but it may clog pores for some and raises concerns about potential impurities from the PEG process.

beautyskincareemollientemulsifier

In plain English

PEG-100 Lanolin is a modified form of lanolin (the natural oil from sheep's wool) that has been treated with polyethylene glycol (PEG) to make it mix with water. This means it can be used in water-based products like lotions and cleansers without feeling greasy. It helps moisturize by forming a protective film on the skin and also helps other ingredients blend together. However, because it's derived from lanolin, it can still be comedogenic (pore-clogging) for some people, and the PEG processing may introduce trace impurities like ethylene oxide or 1,4-dioxane, which are of concern in very high concentrations.

Review score

Safety, usefulness, and evidence

3.5Good
3.5/ 5

Potentially useful with some tradeoffs

The evidence base is useful, but some claims depend heavily on the formula.

Main practical flags: irritation is low; clogging risk is moderate.

Source
semi synthetic
Evidence
moderate
Irritation
low
Clogging risk
moderate
How reviews are scored

Quick decision guide

Useful, but context matters

PEG-100 Lanolin can be useful, but watch for possible clogging concerns.

Plain-English read

Treat this as a practical screening step before you compare products that contain this ingredient.

  1. Step 1Start with the score, then check the irritation and clogging risk before judging PEG-100 Lanolin.
  2. Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
  3. Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.

Score terms in plain English

Irritation risk

low

Less likely to sting, burn, or bother most users, though sensitive skin can still react.

Clogging risk

moderate

May be fine for many users but deserves caution if you are breakout-prone.

Evidence level

moderate

There is useful support, but formula details and claim strength still matter.

What it is

PEG-100 Lanolin is a semi-synthetic ingredient created by reacting lanolin with 100 units of polyethylene glycol. This process makes the naturally water-repellent lanolin water-soluble, allowing it to be used in a wider range of cosmetic formulations.

How it works

In a cosmetic product, PEG-100 Lanolin acts as both an emollient and an emulsifier. As an emollient, it softens and smooths the skin by filling in gaps between skin cells. As an emulsifier, it helps oil and water ingredients mix together, creating a stable, creamy texture. It also helps other ingredients spread evenly on the skin.

Pros

Water-friendly moisturizer

Unlike regular lanolin, PEG-100 Lanolin mixes easily with water, so it hydrates without leaving a heavy, greasy film on the skin.

Improves product feel

It helps create smooth, creamy textures in lotions and cleansers, making them easier to apply and more pleasant to use.

Cons and cautions

Potential for clogged pores

Because it's derived from lanolin, it can be moderately comedogenic, meaning it may block pores and cause breakouts for some people, especially those with oily or acne-prone skin.

Processing impurity concerns

The PEG process can leave behind trace amounts of ethylene oxide or 1,4-dioxane, which are potential carcinogens. Reputable manufacturers purify the ingredient to safe levels, but it's a consideration for those seeking ultra-clean formulations.

Best for

  • People with dry or normal skin looking for a lightweight moisturizer
  • Those who want a stable, creamy cleanser or lotion

Use caution if

  • People with very oily or acne-prone skin
  • Individuals with a known allergy to lanolin or wool

Usage tips

Use in rinse-off products like cleansers or conditioners to minimize pore-clogging risk
If you have sensitive skin, patch test before using a leave-on product containing this ingredient
Look for products from brands that test for and limit 1,4-dioxane impurities

Safety summary

PEG-100 Lanolin is generally considered safe for use in cosmetics at typical concentrations. The main safety concerns are potential comedogenicity for acne-prone skin and trace impurities from the PEG manufacturing process. Reputable brands ensure these impurities are below safe limits. Allergic reactions are rare but possible for those with lanolin sensitivity.

Research notes

The Cosmetic Ingredient Review (CIR) panel has evaluated PEG lanolin derivatives and found them safe for cosmetic use when formulated to be free of 1,4-dioxane and ethylene oxide. Studies show that PEG-100 Lanolin is an effective emollient and emulsifier with low acute toxicity and skin irritation potential. However, there is limited recent research specifically on this ingredient.

Common label clues

Typical concentration
1% to 5%
Regulatory status
Approved for use in cosmetics in the US (FDA) and EU (CosIng) with no specific concentration restrictions, though manufacturers are expected to ensure purity regarding 1,4-dioxane and ethylene oxide.
Common uses
Moisturizers, Cleansers, Hair conditioners, Makeup removers
Environmental note
Lanolin is a byproduct of wool production, making it a renewable resource. However, the PEG process involves synthetic chemicals, and the ingredient may not be fully biodegradable.

Good to know

  • PEG-100 Lanolin is often used in combination with other emulsifiers to create stable formulas
  • It is considered safe by the Cosmetic Ingredient Review (CIR) panel when used as directed, but the panel notes that PEG compounds should be free of harmful impurities

Common questions

What is PEG-100 Lanolin in beauty products?

PEG-100 Lanolin is a modified form of lanolin (the natural oil from sheep's wool) that has been treated with polyethylene glycol (PEG) to make it mix with water. This means it can be used in water-based products like lotions and cleansers without feeling greasy. It helps moisturize by forming a protective film on the skin and also helps other ingredients blend together. However, because it's derived from lanolin, it can still be comedogenic (pore-clogging) for some people, and the PEG processing may introduce trace impurities like ethylene oxide or 1,4-dioxane, which are of concern in very high concentrations.

What does PEG-100 Lanolin do in a beauty product?

In a cosmetic product, PEG-100 Lanolin acts as both an emollient and an emulsifier. As an emollient, it softens and smooths the skin by filling in gaps between skin cells. As an emulsifier, it helps oil and water ingredients mix together, creating a stable, creamy texture. It also helps other ingredients spread evenly on the skin.

Is PEG-100 Lanolin safe for most people?

PEG-100 Lanolin is generally considered safe for use in cosmetics at typical concentrations. The main safety concerns are potential comedogenicity for acne-prone skin and trace impurities from the PEG manufacturing process. Reputable brands ensure these impurities are below safe limits. Allergic reactions are rare but possible for those with lanolin sensitivity.

Who should be careful with PEG-100 Lanolin?

People with very oily or acne-prone skin Individuals with a known allergy to lanolin or wool

Research sources

Cosmetic Ingredient Review (CIR) - Safety Assessment of PEG LanolinOpenFDA - Cosmetics Ingredients DatabaseOpenPubChem - PEG-100 LanolinOpen

Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.