Bu
Butylparaben
Butylparaben
A paraben that keeps bacteria and mold out of a product.
What it does
It’s made from the same acid as methylparaben and propylparaben, with a longer, four-carbon chain. The EU caps it more tightly than the shorter parabens.
The EU’s ingredient database lists it as a preservative (holds back germs in the product).European Commission, CosIng (© European Union, CC BY 4.0) · uses put in plain words by Drop ↗
The evidence, graded
expert consensusUS safety reviewers (2020) judged 20 of 21 parabens, butylparaben among them, safe as used when the parabens in a product add up to 0.8% or less. They reopened the review partly over a rat study in which butylparaben lowered sperm counts in offspring. After weighing the hormone and reproduction studies, they set a new no-effect dose for butylparaben. EU scientists had recommended capping it at 0.14% (as acid); the reviewers found the study behind that figure too limited.Cherian 2020 · International Journal of Toxicology ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Also known as
butyl 4-hydroxybenzoate
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