Benzoic Acid Good Preservative No known benefits Benzoic Acid at a glance Recognised as a safe, well-tolerated preservative Also functions as a pH adjuster in skin care formulations Naturally aromatic but usually isn’t used in high enough potency to impart scent in skin care products Needs to be used in combination with other preservatives for optimum protection Benzoic Acid description Benzoic acid functions as a preservative and pH adjuster in skin care formulations. It is known to be well tolerated and unlikely to cause sensitisation in amounts commonly used. It should be combined with other preservatives in order to prevent broader contamination, particularly in water-based formulas. Benzoic acid primarily serves to reduce growth of fungi. It is not considered very active against bacteria. In 2017, the Cosmetic Ingredient Review Expert Panel looked at personal care products using up to 5% benzoic acid and ruled that this ingredient is safe in cosmetic use. When used as a preservative in skin care products, you’ll find benzoic acid in much lower concentrations, usually between 0.2–0.5%. Note: While benzoic acid can be aromatic in nature, it usually isn’t used in high enough potency to deliver a detectable scent in skin care products. Fun fact: Benzoic acid is naturally found in fruits (berries), nuts, spices and vegetables. Rich sources include strawberries, cayenne pepper, mustard, prunes, cinnamon, and cloves. Benzoic acid is also added to food products as a preservative.