Propylene Carbonate

Propylene carbonate is a small, high-boiling solvent used to dissolve other ingredients and thin out formulas in products like lipstick, eyeshadow, and mascara. Undiluted material caused moderate skin irritation in testing, but at the concentrations actually used in finished products (generally under 20%), CIR's panel found it at most moderately irritating and reaffirmed it safe as used, with no meaningful sensitization or photoirritation seen.

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.