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ETIDRONIC ACID

Description

Etidronic acid, also known as 1-hydroxyethane-1,1-diphosphonic acid (HEDP), is a versatile ingredient used in skincare and cosmetic formulations. This organophosphorus compound functions primarily as a chelating agent and pH adjuster. Its ability to bind metal ions, particularly calcium and magnesium, makes it effective in preventing scale formation and improving the stability of products.

In skincare, etidronic acid serves multiple purposes. It acts as a preservative enhancer, working synergistically with other preservatives to inhibit microbial growth and extend product shelf life. The ingredient also helps maintain the clarity of liquid formulations by preventing precipitation of minerals. Its pH-adjusting properties contribute to creating optimal conditions for other active ingredients to perform effectively.

Etidronic acid is often used in small concentrations, typically below 1%, in various skincare products including cleansers, toners, and serums. It is particularly beneficial in formulations containing hard water-sensitive ingredients. While generally considered safe for cosmetic use, it may cause mild irritation in some individuals with sensitive skin. As with any skincare ingredient, patch testing is recommended before widespread use.