Pe
PEG-150 Pentaerythrityl Tetrastearate
PEG-150 Pentaerythrityl Tetrastearate
A thickener for water-based formulas, most often rinse-off ones.
What it does
It’s a large molecule built from pentaerythritol, stearic acid and long PEG chains. It thickens water-based products, most often rinse-off ones. It’s there for texture, not to change your skin.
The evidence, graded
expert consensusUS safety reviewers (2018) judged PEG-150 pentaerythrityl tetrastearate safe as used. It thickens water-based products, at up to 5% in rinse-off and 1.8% in leave-on products. It’s a large molecule, so it isn’t expected to pass through skin. Undiluted, and as a 25% solution, it caused no irritation or allergy in repeat patch tests on 53 and 52 people. Limits keep the impurities ethylene oxide and 1,4-dioxane to 1 and 5 ppm, which the reviewers judged no concern.Johnson 2018 · International Journal of Toxicology ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
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