thickener · emollient
Trihydroxystearin
Generally safe·Strong evidence
Trihydroxystearin is a wax like triester made by hydrogenating castor oil, used as a fine powder that thickens formulas and gives pressed powders, lipsticks, and creams a smoother glide. CIR's safety review found no skin irritation in clinical testing and no mutagenicity in Ames testing, though the raw ingredient was a mild eye irritant in animal testing, and concluded it is safe as used up to 5%.
Products with Trihydroxystearin
References
Cosmetic information for general education, not medical advice. A verdict is a reading of the published evidence, never a guarantee for your skin: any ingredient can irritate someone, so patch test new products and see a professional if you react. Concern is graded on cited evidence, never on hazard-score lists. See how we score.