What it is
Laureth-3 is a polyethylene glycol ether of lauryl (dodecyl) alcohol bearing an average of three ethylene oxide units, giving it both oil-loving and water-loving regions. This amphiphilic structure lets it emulsify oil and water phases, help solubilize ingredients, and contribute mild surfactant and cleansing action. In sunscreens it is most often used to help build and stabilize emulsions.
Safety & warnings
Laureth surfactants are widely used and generally well tolerated in rinse-off and leave-on products. As an ethoxylated ingredient it is manufactured to limit residual 1,4-dioxane, a process-related impurity; high levels of low-ethoxylate surfactants can be mildly irritating to very sensitive or compromised skin depending on the formula.
Origin & sourcing
Synthetic: produced by ethoxylation of lauryl alcohol, which itself may be derived from petrochemical or vegetable (e.g., coconut or palm) sources.
Questions everyone asks
What does Laureth-3 do?
It acts as a nonionic surfactant and emulsifier, helping blend oil and water phases and solubilize ingredients.
What is it made from?
It is made by attaching ethylene oxide units to lauryl alcohol, which can come from vegetable or petrochemical sources.