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2,3-Butanediol
2,3-ButanediolHydrator
A glycol that helps dissolve ingredients and draws in water.
What it does
It’s a close cousin of butylene glycol, with its two alcohol groups side by side in the middle of a four-carbon chain.
The EU’s ingredient database lists it as a humectant (helps hold in moisture) and a solvent (dissolves other ingredients).European Commission, CosIng (© European Union, CC BY 4.0) · uses put in plain words by Drop ↗
The evidence, graded
expert consensusUS safety reviewers (2024) assessed 10 small glycols called alkane diols. They judged 7 safe as used, but had too little data to judge the other 3, 2,3-butanediol among them, which no product was reported to use. For it they asked for use amounts, 28-day skin toxicity studies, skin and reproductive toxicity data, and tests for DNA damage in mammal cells unless it is used at low amounts. Undiluted, it didn’t irritate rabbit eyes.Scott 2024 · 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
2,3-butylene glycol
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