Pe
PEG-400
PEG-400
A large PEG that binds a formula, helps oil and water stay mixed and dissolves other ingredients.
What it does
On a label, PEG-400 is a polyethylene glycol (PEG) with chains about 400 units long. It’s easy to mix up with polyethylene glycol 400, a much smaller PEG whose label name is PEG-8.
The evidence, graded
expert consensusUS safety reviewers (2010) judged PEGs safe as used, PEG-400, PEG-14M, PEG-45M and PEG-90M among them, which bind formulas and help keep oil and water mixed. PEGs aren’t irritants or allergens on normal skin. On burns, where both outer layers of skin are gone, PEGs can get in and may harm the kidneys, so products high in PEGs shouldn’t go there. They asked makers to remove ethylene oxide and 1,4-dioxane.Cosmetic 2010 · Cosmetic Ingredient Review ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
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