What Is It?

Oleth-2, -3, -4, -5, -6, -7, -8, -9, -10, -11, -12, -15, -16, -20, -23, -25, -30, -40, -44, and -50 are polyethylene glycol ethers of oleyl alcohol in which the number in the name is the average number of ethylene oxide units. In cosmetics and personal care products, the Oleth ingredients are used in the formulation of skin care products, makeup and hair care products.

Why Is It Used?

The Oleth ingredients clean skin and hair by helping water to mix with oil and dirt so that they can be rinsed away. These ingredients also help to form emulsions by reducing the surface tension of the substances to be emulsified and help ingredients to dissolve in liquids in which they would not normally dissolve.

Scientific Facts

The Oleth ingredients are polyethylene glycol ethers of oleyl alcohol. Their physical from ranges from liquids to waxy solids. The water solublity of the Oleth ingredients increases as the content of ethylene oxide increases.

Safety Information

The safety of Oleth-2, -3, -4, -5, -6, -7, -8, -9, -10, -11, -12, -15, -16, -20, -23, -25, -30, -40, -44 and -50, has been assessed by the Cosmetic Ingredient Review (CIR) Expert Panel. The CIR Expert Panel evaluated the scientific data and concluded that the Oleth ingredients, were safe in the present practices of use.

CIR Safety Review: In assessing the safety of the Oleth ingredients, the CIR Expert Panel relied extensively on earlier safety evaluations of the parent compounds, oleyl alcohol and polyethylene glycol (PEG). Consistent with information on other surfactants, data on the Oleth ingredients indicated evidence of mild to moderate eye and skin irritation. These ingredients were not cosidered to be reproductive or developmental toxicants. Based on a a study showing kidney effects in burn patients treated with an ointment made mostly of polyethylene glycol, the CIR Expert Panel noted that the stipulation in the PEG safety evaluation, “not to be used on damaged skin,” should also be applied to the Oleth ingredients. The CIR Expert Panel also noted that product formulaters should be aware that some studies showed that the Oleth ingredients may increase the penetration of other ingredients.

The CIR Expert Panel acknowledged the use of Oleth ingredients in hair sprays but after learning that most of the particles produced by products were too large to enter the lungs, and considering the concentrations used in these products, the Oleth ingredients were considered to be safe for use in aerosolized products. Small amounts of 1,4-dioxane, a by-product of ethoxylation, may be found in the Oleth 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.

The Oleth ingredients may be used in cosmetics and personal care products marketed in Europe according to the general provisions of the Cosmetics Regulation of the European Union.

Link to the EU Cosmetic Regulation: 

More Scientific Information

The Oleth ingredients belong to a chemical class known as alkoxylated alcohols. Alkoxylated alcohols are ethers formed from the reaction of an alcohol with an alkylene oxide, in this case, ethylene oxide. Because the ether formed from the reaction of one molecule of an alcohol with one molecule of the alkylene oxide is also an alcohol, the reaction with the alkylene oxide can continue until the latter is consumed. In this synthesis, the hydroxyl group of the starting alcohol is converted to an ether linkage; however, the end products of the reactions are also alcohols since they contain at least one terminal hydroxyl group. The Oleth ingredients are used as surfactants (cleansing, emulsifying, and solubilizing agent) in cosmetics and personal care products.