Sodium Metaphosphate Middel Emulsifier No known benefits Sodium Metaphosphate at a glance Synthetic emulsifier and pH adjuster Also used in the dental field Deemed safe as used in cosmetics Requires careful formulation to avoid levels proven to irritate skin Serves as a chelating agent for some metals Sodium Metaphosphate description Sodium metaphosphate is a synthetic ingredient used in cosmetics formulations as an emulsifier and a pH adjuster, and in dental preparations as a mild abrasive. It’s typically produced by reacting salt (sodium chloride) with phosphoric acid in a 1:1 ratio. The independent Cosmetic Ingredient Review panel has ruled sodium metaphosphate safe to use in cosmetics when it is formulated to be non-irritating. Tests done for the safety assessment found that sodium metaphosphate in a 1% solution was mildly irritating to the skin of human subjects. This ingredient is used in concentrations of 0.01-9.6%, with the larger concentrations being in rinse-off products. As a chelator in topical products, the use level is usually less than 0.1%.