alpha-Terpineol on your skin: a safety profile

What is alpha-terpineol?

The IUPAC name is 2-(4-methylcyclohex-3-en-1-yl)propan-2-ol.

Also known as: 2-(4-methylcyclohex-3-en-1-yl)propan-2-ol, p-Menth-1-en-8-ol, 1-p-Menthen-8-ol, Terpineol 350.

IUPAC name

2-(4-methylcyclohex-3-en-1-yl)propan-2-ol

CAS number

98-55-5

Molecular formula

C10H18O

Molecular weight

154.25 g/mol

SMILES

CC1=CCC(CC1)C(C)(C)O

PubChem CID

17100

Regulatory consensus

2 regulatory and scientific bodies have classified alpha-Terpineol. The classifications differ — that's the data.

Regulators apply different standards of evidence — animal-data weighting, exposure-pattern assumptions, epidemiological power thresholds — which is why two scientific bodies can review the same data and reach different conclusions. The disagreement is the data.

Where you encounter alpha-terpineol

• Personal Care — perfume, soap, lotion, shampoo
• Consumer Products — cleaning products, air fresheners
• Fragrance — perfume, cologne, scented personal care products, household fragrance products, candles
  Identified in Fragrance Ingredient Safety Priority Research database (2,325 ingredients)

Safer alternatives

Lower-risk approaches that achieve a similar outcome to alpha-Terpineol:

• Linalool
  Trade-offs: Alternative fragrance ingredient; individual safety profile should be assessed per IFRA standards; sensitization potential varies by compound; patch testing recommended for sensitive individuals.
  Relative cost: 1.2-2×
• Dihydromyrcenol
  Trade-offs: Removes 95-99% of dissolved contaminants including metals, PFAS, nitrates; wastes 2-4 gallons per gallon produced (improving with newer systems); removes beneficial minerals; $0.05-0.25/gallon; requires pre-treatment for longevity.
  Relative cost: 1.2-2×

Frequently asked questions