At a glance
- CAS number
- 100-51-6
- INCI name
- Benzyl Alcohol
- Function
- preservative, solvent, fragrance, viscosity controlling
- Typical use level
- 0.1%–1%
- Solubility
- both
- Stable pH
- 3–8
CAS number and synonyms are sourced from PubChem. Function, usage levels, pH and compatibility are AI-assisted formulation guidance — verify against your supplier's technical data sheet and applicable regulations before use.
Also known as
benzyl alcohol phenylmethanol benzenemethanol phenylcarbinol Benzoyl alcohol Benzenecarbinol Hydroxytoluene alpha-Toluenol Phenylmethyl alcohol (Hydroxymethyl)benzene Phenolcarbinol alpha-hydroxytoluene
Compatibility
Works well with:
Phenoxyethanol Ethylhexylglycerin Dehydroacetic Acid Potassium Sorbate Sodium Benzoate Glycerin Niacinamide Hyaluronic Acid Carbomer Xanthan Gum
Use caution with:
Oxidizing Agents Strong Acids Strong Bases Methylchloroisothiazolinone
Benzyl alcohol can oxidize to benzaldehyde and benzoic acid over time when exposed to air or oxidizing agents, reducing efficacy and potentially causing irritation. It is often used synergistically with other preservatives such as phenoxyethanol or dehydroacetic acid for broader spectrum coverage. Combination with methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) is generally avoided due to overlapping sensitization concerns.
Formulation notes
EU Cosmetics Regulation restricts Benzyl Alcohol to a maximum of 1% as a preservative; it is also a listed fragrance allergen (Annex III) requiring declaration on-label when above 0.001% in leave-on and 0.01% in rinse-off products. Generally considered safe at low preservative levels but can be a skin sensitizer at higher concentrations. Not recommended for use in products intended for infants under 3 years.
Related ingredients
- UreaHumectant
- Caprylyl GlycolPreservative
- ChlorphenesinPreservative
- BisabololActive
- Butylene GlycolHumectant
- Caprylic/Capric TriglycerideEmollient