Benzoic acid is the simplest carboxylic aromatic acid found in tree bark, as well as fruits and berries in low quantities as a natural defense against fungus. This natural preservative has been known for centuries since, in 1556, Nostradamus discovered it in benzoin gum (a balsamic resin from Snowbell tree bark).
Today, Benzoic acid is used as a food-grade FDA-approved preservative effective against yeast, mold, and some bacteria. In skin care preparations, perfume, and decorative cosmetics, it is also used as a preservative that enhances the shelf-life of a product inhibiting the growth of microorganisms, and is effective after opening a packaging.
In combination with other preservatives such as Phenoxyethanol and Benzyl alcohol, Benzoic acid acts as preservative-booster improving preservation effectiveness. It is soluble in many bases and suitable for almost all skin and hair care products, including baby care preparations.
It does not tend to be accumulated in the skin or body and is an environment-friendly biodegradable ingredient. There is a cheaper synthetic analog of Benzoic acid, but in high-end formulations is used a naturally derived and Ecocert, COSMOS, and Nature certified ingredient.