Is Propylene Glycol in Cosmetics Safe?

What is propylene glycol and what is it used for?

Propylene glycol (INCI: Propylene Glycol) is a small, diol organic alcohol widely used across the cosmetic, pharmaceutical and food industries. In cosmetics it serves several important functions:

• Humectant — binds water, keeps the product from drying out and hydrates the skin
• Solvent — helps dissolve active ingredients such as vitamins and plant extracts
• Penetration enhancer — increases the absorption of other active substances into the skin
• Preservative — at higher concentrations it has antimicrobial properties

Propylene glycol is everywhere: you'll find it in creams, serums, toners, shampoos, antiperspirants, toothpastes and many medicines. It is approved as a food additive (E1520) by the European Food Safety Authority (EFSA).

What do science and regulators say about its safety?

The SCCS (Scientific Committee on Consumer Safety) and the Cosmetic Ingredient Review (CIR) have assessed propylene glycol many times. Their conclusions are consistent: propylene glycol is safe at the concentrations used in cosmetics, which typically range from 1% to 20%.

Regulation (EC) No 1223/2009 does not place propylene glycol on the list of prohibited or restricted substances. The European Commission's CosIng database classifies it as an approved ingredient with no general restrictions.

Where do the safety concerns come from?

Many of the warnings about propylene glycol circulating online stem from its industrial uses (as an antifreeze) or from studies carried out at very high concentrations that are never used in cosmetics. The dose makes the poison — that principle applies fully here. The concentrations used in cosmetics are many times lower than the doses shown to have any toxic effects.

• It shows no carcinogenic or mutagenic activity at typical cosmetic concentrations
• It does not accumulate in the body — it is rapidly metabolised
• Studies in animals and humans have found no teratogenic effects at cosmetic doses

When can propylene glycol be a problem?

Despite its strong safety profile, propylene glycol can trigger reactions in some people:

• Skin irritation — at higher concentrations (above 10–30%) it can irritate damaged or very sensitive skin, especially when applied under occlusion
• Contact dermatitis — rare, estimated at less than 2–3% of the population; allergic contact dermatitis to propylene glycol can be identified with a patch test
• Atopic skin — people with atopic dermatitis may react to propylene glycol even at low concentrations; manufacturers of cosmetics designed for atopic skin often replace it with butylene glycol or polyethylene glycol

Note: this article is for informational purposes and does not replace a dermatological consultation. If you suspect an allergy to a specific ingredient, see a dermatologist for a patch test.

How to spot propylene glycol on the label?

On the INCI list, look for the name Propylene Glycol. Don't confuse it with similar-sounding ingredients:

• Butylene Glycol — a four-carbon analogue, often used as a substitute for people who react to PG
• Polyethylene Glycol (PEG) — a completely different molecule, a polymer of ethylene oxide
• Dipropylene Glycol — a dimer of propylene glycol, gentler

In our ingredient encyclopedia you'll find detailed profiles of each of these compounds, with safety ratings and their roles in formulations.

Alternatives to propylene glycol

If your skin reacts badly to propylene glycol, it's worth looking for face creams with alternative humectants:

• Butylene Glycol — gentler and often well tolerated by sensitive skin
• Glycerin (Glycerin) — a classic, safe humectant
• Squalane (Squalane) — an emollient well tolerated by most skin types
• Sodium PCA — a humectant naturally present in the skin's NMF

Summary

Propylene glycol is a safe ingredient for the vast majority of consumers at the concentrations used in cosmetics. Its bad reputation stems mainly from myths and misunderstandings about its industrial uses. People with sensitive or atopic skin may prefer formulas without this ingredient — and they have every right to, even though it is not a medical necessity.

Check the ingredients in your cosmetics →