CIR Safety Review: In preparing the report on Laureth-4 and Laureth-23, the CIR Expert Panel also reviewed safety test data on closely related Laureths and other ethoxylated lauryl alcohol compounds that are in consumer products, but not in cosmetics and personal care products. Developmental toxicity, multiple generation and fertility data, as well as mutagenicity data were all negative for these compounds. These data supported the CIR Expert Panel’s conclusion that Laureth-4 and Laureth-23 were safe for use in cosmetics and personal care products.

Small amounts of 1,4-dioxane, a by-product of ethoxylation, may be found in the Laureth ingredients. The potential presence of this material is well known and can be controlled through purification steps to remove it from the ingredients before blending into cosmetic formulations.

Link to more information about what the Food and Drug Administration (FDA) is doing to assure that cosmetics do not contain unsafe levels of 1,4-dioxane.
http://www.fda.gov/Cosmetics/ProductandIngredientSafety/Pote...

Laureth-4 and Laureth-23 may be used in cosmetics and personal care products marketed in Europe according to the general provisions of the Cosmetics Directive of the European Union.
Link to the EU Cosmetics Directive: http://ec.europa.eu/consumers/sectors/cosmetics/documents/di...

Laureth-4 is the polyethylene glycol ether of lauryl alcohol that contains an average value of 4 repeating ethylene oxide units, while Laureth-23 contains an average of 23 repeating ethylene oxide units. These ingredients are useful in cosmetic and pharmaceutical products as surfactants, emulsifiers and solubilizers. Their use is particularly attractive in light of their chemical inertness to hydrolytic decomposition.