laureth

Laureth is a class of nonionic surfactants derived from lauryl alcohol by ethoxylation with ethylene oxide. The general structure is RO-(CH2-CH2-O)n-H, where R is a C12- to C14-16 alkyl group. The “laureth” designation is followed by a number that denotes the average number of ethoxy units, with common homologues including laureth-3, laureth-4, laureth-6, and laureth-10. These are alkyl ether ethoxylates and are widely used as surfactants and emulsifiers.

Manufacture involves catalytic ethoxylation of lauryl alcohol, producing a range of products with varying hydrophilic-lipophilic balance (HLB). The specific properties, such as solubility and foaming, depend on the degree of ethoxylation. Purification is important because residual impurities like 1,4-dioxane can be present; many manufacturers apply purification steps to minimize such contaminants in consumer products.

Uses of laureth surfactants are common in cosmetics and household cleaners as mild cleansing agents, foaming enhancers, emulsifiers, and solubilizers for fragrances and essential oils. They are often found in shampoos, body washes, facial cleansers, and detergents, sometimes in combination with other surfactants to adjust viscosity and foam.

Safety and regulatory: Laureth compounds are generally regarded as safe for use in cosmetic and personal care products at standard concentrations, but they can cause skin or eye irritation at higher levels. They are not typically classified as carcinogenic. In some jurisdictions, residual solvents like 1,4-dioxane must be controlled or limited through purification and testing. They can be incompatible with certain cationic ingredients.

Environment: Laureth surfactants are designed to be biodegradable, but environmental impact depends on chain length and impurities. In wastewater, they break down into shorter ethoxylated fragments and ultimately mineralize under aerobic conditions; aquatic toxicity is a consideration in formulation.