Citronellol

Citronellol is a fragrance allergen (terpene alcohol) used at low concentrations in scented products, but it is a well-documented cause of allergic contact dermatitis on patch testing, especially in eczema-prone and barrier-impaired skin. While not typically a primary irritant at very low doses, its sensitization potential and the common cumulative exposure from multiple fragranced products make clinically meaningful reactions plausible. For high-sensitivity populations, I treat its risk as significant and recommend avoidance rather than "gentle" use. Safety Notes: Citronellol is most commonly present as a trace fragrance allergen/constituent of perfume compositions or essential oils in finished skincare, with many leave-on and rinse-off products listing it at very low disclosed levels around ~0.0001–0.01% typical of allergen-level declaration. Higher concentrations occur in strongly fragranced consumer products (e.g., body sprays, fragranced lotions/creams, soap bars) or when citronellol-rich natural fragrances are used heavily, where finished-product levels can reach ~0.1–1.0% in OTC items; above this becomes uncommon due to odor impact and sensitization/IFRA-style fragrance safety constraints, especially for leave-on products.