preservative
1,2-Hexanediol
Paraben alternative and multifunctional preservative booster widely adopted in K-beauty and clean-positioned formulas. Combines antimicrobial activity with humectant and solubiliser function.
Benefits
- Broad-spectrum antimicrobial against bacteria and yeast
- Mild humectant
- Solubilises actives and fragrance components
- Enhances co-preservative efficacy
- Good tolerability at cosmetic concentrations
Example uses
- Water-based peptide/PDRN serums
- Essence and toner formulations
- Sheet mask solutions
- Lightweight gel moisturisers
- Mist sprays
Mechanism of action
Disrupts microbial cell membrane integrity by intercalating into the lipid bilayer, increasing permeability and causing cytoplasmic leakage. Synergistic FIC effects with caprylyl glycol demonstrated in checkerboard assays. Humectant activity secondary via hydroxyl group hydrogen bonding.
Clinical evidence · Moderate
Safety assessed by SCCS; antimicrobial efficacy supported by MIC studies and checkerboard assays.
Effective concentration range
0.5–2%
Formulation notes
Effective pH 4–7; best paired with other preservation systems. May affect viscosity in polymer-thickened systems at higher loads.
Watchouts
Above 2% can cause transient irritation in compromised-barrier skin. Rare contact dermatitis documented.
Stacks with
Conflicts with
Controversies & overclaims
Often communicated as naturally derived despite petrochemical synthesis.
Market positioning
Sold as gentle paraben-free preservative. Synthetic origin and occasional sensitisation at higher concentrations underreported.
Comedogenicity
0 / 5
Sensitisation risk
Low
INCI & aliases
1,2-Hexanediol
hexane-1,2-diol · 1,2-dihydroxyhexane
Clean beauty perception
Accepted as paraben-free option though synthetically derived. Some brands misattribute botanical provenance.
Related ingredients
Graph relationships
Timeline