Po
Polyquaternium-11
Polyquaternium-11
A hair-product polymer that forms a film and cuts static.
What it does
It’s a polymer with a positive charge. The EU lists it to form a film and to reduce static.
The evidence, graded
expert consensusUS safety reviewers’ 1983 report describes polyquaternium-11 as a polymer used in hair products at up to 50%. In repeated patch tests on people at up to 50% it caused no allergy and only rare, passing irritation, and the reviewers judged it safe as used. In 2023 they looked again, when leave-on products used it at up to 2.9%, and kept that verdict.Cosmetic 1983 · Journal of the American College of Toxicology 2(5):161-178 (CIR portal copy) ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
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