peeling solution for face. Salicylic Acid is a Beta Hydroxy Acid (BHA), derived from natural sources such as willow tree bark, wintergreen leaves, or sweet birch bark. Salicylic Acid is an effective exfoliant, which has the ability to penetrate oily skin and clogged pores for a deep cleansing. The Acid works towards removing dead skin cells and excessive sebum, which helps reveal fresher, more even-toned skin.