Bu
Butylated Hydroxyanisole (BHA)
BHA · Butylated HydroxyanisoleAntioxidant
An antioxidant that keeps a formula’s oils from going off. “BHA” in an ingredient list means this, not salicylic acid.
What it does
It mops up the reactive molecules that make oils spoil, so it protects the product itself. The EU also lists it as a fragrance ingredient. Skincare sold as a “BHA” exfoliant means salicylic acid, which the ingredient list prints as Salicylic Acid.
The evidence, graded
expert consensusThe EU CosIng record for BHA (chemical name tert-butyl-4-methoxyphenol, CAS 25013-16-5) lists two functions: antioxidant and fragrance. It lists no cosmetic restriction. The SCCS adds that cosmetic products often contain synthetic antioxidants like BHA to prevent the oxidation of fats and oils.EU 2026 · CosIng, European Commission database of cosmetic ingredients ↗
expert consensusSCCS/1682/25 (final, 26 March 2026) assessed BHA over potential endocrine-disrupting properties. It considers BHA safe in leave-on and rinse-off products up to 0.07%, for dermally applied products only, not oral care or products that may be inhaled. It found weak anti-estrogenic activity and some sperm effects in in vivo studies of limited quality, but judged the evidence not robust enough to suggest an endocrine mode of action. It regards the skin sensitisation risk as negligible.SCCS 2026 · European Commission SCCS (final version, 26 March 2026) ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
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