Steareth-21 is a white, waxy compound that functions as a surfactant, emulsifier and solubilizing agent, all of which helps create optimal aesthetics for skin care formulations.
What is STEARETH-21 used for?
Steareth-21 is used as an emulsifier in cosmetics and personal care products, including makeup, lotions, personal cleanliness products and deodorants, as well as suntan, fragrance, skin, eye and hair care products. It is also used as cleansing agent in shampoo, shower gel, face wash; as an emulsifying agent to promotes the formation of intimate mixtures between immiscible liquids by modifying the interfacial tension (water and oil) in creams, lotions; and as a surfactant to reduce the surface tension of cosmetics and contributes to the even distribution of the product during use.
Origin
Steareth ingredients are prepared by interacting with the chemical intermediate gas ethylene oxide with stearyl alcohol, a process which forms an entirely new stable compound. The number that comes after (for instance, 21) indicates the average number of ethylene oxide units used in the preparation.
Safety profile
In 2012, the independent Cosmetic Ingredient Review panel ruled that steareth-21 is safe as used in cosmetics in amounts up to 7%. There have been concerns about the safety of steareth ingredients because toxic 1,4-dioxane, a by-product of ethoxylation, can be produced; however, this is eliminated through purification processes.