DO NOT USE if you are allergic to Asprin.This serum now has a brownish tint to it. We had to change suppliers for the water soluble salicylic acid.We have had inquiries over the years for a water soluble Salicylic Acid and we now have the opportunity to have this customer tested to see if we should add this to our finished product line. We hope this will be a successful addition for customers who can't tolerate organic alcohol (excellent penetration enhancer).INCI: 2-Hydroxybenzoic acidThis salicylic acid is the synthesized form which is the same chemical structure as that of white willow bark.
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