Propylene Glycol Isoceteth-3 Acetate

Propylene Glycol Isoceteth-3 Acetate is a nonionic surfactant/solubilizer-emollient ester typically used at low percentages, where it is usually well tolerated but can contribute to barrier disruption when combined with other cleansing agents. Surfactant-like ingredients and ethoxylated derivatives have a measurable rate of irritant reactions in sensitive/eczema-prone skin, especially with leave-on exposure or compromised barriers. Given the lack of extensive, ingredient-specific clinical irritancy data and the known behavior of similar solubilizers, a mild irritancy score is the safest clinically-aligned choice. Safety Notes: Propylene Glycol Isoceteth-3 Acetate is used commercially as a solubilizer/emollient and fragrance-oil carrier, where it often appears at very low levels (~0.05–0.5%) in leave-on moisturizers/serums primarily to aid solubilization and sensory slip. In higher-solvent or fragrance-bearing systems (e.g., makeup primers, facial oils/essences, and some rinse-off cleansers) it is used more substantively as part of the oil/solvent phase, with observed consumer-available products reaching ~5–8% while still maintaining acceptable stability and skin feel. There is no specific EU/FDA maximum concentration limit for this ingredient as such; practical upper use is driven by irritation potential and compatibility with the overall surfactant/oil system, especially in leave-on products.