2,3-Butanediol is a small diol used in cosmetics primarily as a humectant and solvent that helps retain moisture and aid the dissolution of other ingredients. It also offers mild antimicrobial properties that can support product preservation.
| Reported effect | How often | Notes |
|---|---|---|
Mild skin irritation | Rare | Transient redness or stinging, more likely at higher concentrations or on compromised skin. |
Contact dermatitis / allergic sensitization | Very rare | Isolated reports; glycol-type diols are generally considered low sensitizers. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.