Menthone

Menthone is a mint-derived fragrance/essential-oil constituent used at low levels for scent but with well-documented irritant potential on compromised or reactive skin, especially in leave-on products. Clinical and patch-test literature on mint terpenoids shows frequent stinging/burning and irritant reactions (and occasional sensitization), with higher risk in eczema due to barrier disruption and cumulative exposure from multiple fragranced products. Given patient-safety considerations and its role as a non-essential fragrance component, I score it as a significant irritant. Safety Notes: Menthone is most often present at trace levels as a constituent of peppermint/mint essential oils or fragrance blends in mass-market lotions, cleansers, and toners, where finished-product menthone can fall into the ~0.0001–0.01% range depending on the oil/fragrance load and composition. In high-sensory “cooling” OTC products (e.g., foot/leg gels, aftershaves, scalp tonics) and strongly fragranced balms, menthone can reach the upper end around ~0.1–1.0% when used as part of a mint/aroma complex, with higher levels limited by irritation/sensitization and IFRA-style fragrance safety constraints, especially for leave-on products.