Triolein

Triolein is a non-volatile triglyceride (glycerol trioleate) used as an emollient/skin-conditioning lipid, typically at low-to-moderate percentages in creams and oils, and it is generally well tolerated because it is not a reactive active and has minimal inherent irritancy in patch testing. In highly eczema-prone or compromised skin, any lipid can occasionally feel stinging if the barrier is severely disrupted or if the formula promotes oxidation byproducts, so I do not score it as near-inert. Overall, its direct irritation potential is low, consistent with a very gentle emollient ingredient. Safety Notes: In commercial skincare, triolein is most often present as a minor constituent of vegetable oils (e.g., olive oil) or lipid blends and may appear on INCI lists at trace/low levels (~0.01–0.5%) in emulsions, cleansers, and serums where it functions as an emollient/skin-conditioning lipid. At the high end, consumer-available anhydrous oils and oil-based cleansing products can be effectively neat triglycerides; products marketed as “triolein” or highly purified triglyceride/oil bases can reach ~90–100% in leave-on body oils or oil cleansers. No specific FDA/EU maximum concentration limit is established for triolein as a cosmetic ingredient; practical limits are driven by product format (emulsion vs anhydrous) and sensory/stability considerations.