Sodium laureth sulfate


Sodium laureth sulfate, an accepted contraction of sodium lauryl ether sulfate, is an anionic detergent and surfactant found in many personal care products. SLES is an inexpensive and very effective foaming agent. SLES, sodium lauryl sulfate, ammonium lauryl sulfate, and sodium pareth sulfate are surfactants that are used in many cosmetic products for their cleaning and emulsifying properties. It is derived from palm kernel oil or coconut oil.
Its chemical formula is. Sometimes the number represented by n is specified in the name, for example laureth-2 sulfate. The product is heterogeneous in the number of ethoxyl groups, where n is the mean. Laureth-3 sulfate is common in commercial products.

Production

SLES is prepared by ethoxylation of dodecyl alcohol, which is produced industrially from palm kernel oil or coconut oil. The resulting ethoxylate is converted to a half ester of sulfuric acid, which is neutralized by conversion to the sodium salt. The related surfactant sodium lauryl sulfate is produced similarly, but without the ethoxylation step. SLS and ammonium lauryl sulfate are commonly used alternatives to SLES in consumer products.

Safety

Tests in the US indicate that it is safe for consumer use. The Australian government's Department of Health and Ageing and its National Industrial Chemicals Notification and Assessment Scheme have determined SLES does not react with DNA.

Irritation

Like many other detergents, SLES is an irritant. It has also been shown that SLES causes eye or skin irritation in experiments conducted on animals and humans. The related surfactant SLS is a known irritant.

1,4-Dioxane contamination

Some products containing SLES contain traces of 1,4-dioxane, which is formed as a by-product during the ethoxylation step of its production. 1,4-Dioxane is classified by the International Agency for Research on Cancer as a Group 2B carcinogen: possibly carcinogenic to humans. The United States Food and Drug Administration recommends that these levels be monitored, and encourages manufacturers to remove 1,4-dioxane, though it is not required by federal law.