Sodium Salicylate

What-it-does: preservative

The sodium salt of salicylic acid. CosIng (the official EU cosmetic ingredient database) says that it's a preservative and helps to make the product taste bad (called denaturant), while some manufacturer claims that it has exfoliating properties and is antimicrobial. It's good to know, that the salt of an exfoliant is kind of a neutralised form, so if you want to go for exfoliation stick to the pure acid.