Safety Assessment of Inorganic Hydroxides as Used in Cosmetics
Christina L. Burnett, Wilma F. Bergfeld, D. Belsito, Ronald A. Hill, Curtis D. Klaassen, D.C. Liebler, James G. Marks, Ronald C. Shank, Thomas J. Slaga, Paul W. Snyder, Lillian J. Gill, Bart Heldreth
Abstract
The Expert Panel for Cosmetic Ingredient Safety (Panel) reviewed the safety of inorganic hydroxides, which function in cosmetics primarily as pH adjusters. Representatives from the cosmetic industry have indicated these ingredients are used in depilating and hair waving/straightening formulations to raise pH values. The Panel considered relevant data related to these ingredients. The Panel concluded that these inorganic hydroxides are safe in hair straighteners and depilatories under conditions of recommended use; users should minimize skin contact. These ingredients are safe for all other present practices of use and concentration described in this safety assessment when formulated to be nonirritating.