PEG
Reviewed by Daisy · Last updated 18 Aug 2026
Also known as: polyethylene glycol
Versatile ingredient used as a cleansing agent, emollient, and emulsifier | Considered safe for skin when used in cosmetic formulations
Addresses
EWG Safety Score
What Is PEG?
PEG is an acronym for polyethylene glycol, an amazingly versatile ingredient in skin care products because of the many uses it has and its broad compatibility with different types of ingredients. PEG is often mixed with an array of hydrating emollients, beneficial fatty acids, and cleansing agents. In these various combinations, a PEG can be used in gentle cleansers, elegant moisturizers, sunscreens, and unique treatment products.
The safety of PEG in its various forms has recently been questioned. The primary concern is that they can contain problematic impurities such as ethylene oxide and 1,4 dioxane. Both of these are by-products from the manufacturing process, not something natural to any form of PEG. Although this was once a concern, reputable cosmetic ingredient suppliers have long since eliminated these impurities from the finished ingredient, which makes PEGs safe for skin.
What is most notable about the various forms of PEG studied to date is they have been shown to be non-irritating for skin or eyes, even when used in concentrations greater than what most skin care products contain. PEGs also widely considered non-toxic because they do not penetrate intact skin. However, as is true for even the gentlest ingredients, when skin is inflamed or compromised, the risk of irritation is increased.
If you've seen conflicting information about PEG ingredients, it's important to know that the conclusions were not applicable to how PEGs are used in skin care products. These studies involved feeding a large amount of PEG to animals or applying very high doses (literally hundreds of magnitudes greater than what is used in topical products) to mouse skin.
Clinical Evidence & References
Published Research
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International Journal of Toxicology, September-October 2018 Supplement, pages 10S-60S [URL Not Found]
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November-December 2014 Supplement, pages 13S-39S [URL Not Found]
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September-October 2012 Supplement, pages 169S-244S [URL Not Found]
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Toxicological Research, June 2015, pages 105-136 [URL Not Found]
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Skin Pharmacology and Physiology, January 2015, pages 12-21 [URL Not Found]
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Drug Metabolism and Disposition, January 2007, pages 9-16 [URL Not Found]
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Experimental Dermatology, October 2006, pages 801-807 [URL Not Found]
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Toxicology, October 2005, issues 1-2, pages 1-38 [URL Not Found]
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Archives of Dermatological Research, June 2001, pages 302-307 [URL Not Found]
Frequently Asked Questions
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