Isostearyl Alcohol

What Is It?

Cetearyl Alcohol, Cetyl Alcohol, Myristyl Alcohol and Behenyl Alcohol are white, waxy solids. Isostearyl Alcohol is a clear liquid. Cetyl Alcohol and Stearyl Alcohol are the two major components of Cetearyl Alcohol. These ingredients are all fatty alcohols and that are widely used in cosmetics and personal care products, especially in skin lotions and creams.

Why Is It Used?

Cetearyl Alcohol and the other fatty alcohols keep an emulsion from separating into its oil and liquid components. These ingredients are also used to alter the thickness of liquid products and to increase foaming capacity or to stabilize foams.

Scientific Facts

Cetearyl, Cetyl, Myristyl and Behenyl Alcohols are straight-chain alcohols. Isostearyl Alcohol is a branched chain alcohol. Cetearyl Alcohol is a mixture of mostly of Cetyl and Stearyl Alcohols, which are fatty alcohols that occur naturally in small quantities in plants and animals.

Myristyl Alcohol is a 14 carbon chain. Cetyl Alcohol has 16 carbons, while Stearyl and Isostearyl Alcohols have 18 carbons. Behenyl Alcohol is the largest fatty alcohol in this group with 22 carbons.

Safety Information

The Food and Drug Administration (FDA) includes synthetic fatty alcohols including Cetyl Alcohol, Stearyl Alcohol and Myristyl Alcohol on its list of food additives permitted for direct addition to food as multipurpose food additives. Synthetic fatty alcohols are also permited as indirect food additives as adjuvants and production aids.

The safety of Cetearyl Alcohol, Cetyl Alcohol, Isostearyl Alcohol, Myristyl Alcohol and Behenyl Alcohol has been assessed by the Cosmetic Ingredient Review (CIR) Expert Panel. The CIR Expert Panel evaluated the scientific data and concluded that these fatty alcohols were safe for use as cosmetic ingredients.

In 2005, the CIR Expert Panel considered available new data on Cetearyl Alcohol and the other fatty alcohols and reaffirmed the above conclusion.

CIR Safety Review: The CIR Expert Panel noted that much is known about the biological activities of fatty acids and long-chain aliphatic alcohols and esters.

The toxicological data for the five long-chain aliphatic alcohols included in this report (Cetearyl Alcohol, Cetyl Alcohol, Isostearyl Alcohol, Myristyl Alcohol, Behenyl Alcohol) revealed no significant toxicity. For example, Cetyl Alcohol was not mutagenic. Formulations containing these fatty alcohols were not dermal irritants or sensitizers. Assuming that the five ingredients are of the same grade of purity, the similar chemical structure permits extrapolation of data for one of the alcohols to the remaining four alcohols. Thus, the CIR Expert Panel considered it reasonable to assume that the fatty alcohols reviewed in this report have equivalent biological activity.

FDA: Link to Code of Federal Regulations for synthetic fatty alcohols including Cety, Stearyl and Myristyl Alcohols  

If they are derived from plants, Cetearyl, Cetyl, Isostearyl, Myristyl and Behenyl Alcohols 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.

Ingredients of animal origin must comply with European Union animal by-products regulations.

More Scientific Information

Cetearyl, Cetyl, Isostearyl, Myristyl and Behenyl alcohols are fatty alcohols. They are produced from natural fats and oils by reduction of the fatty acid carboxyl group (-COOH) to the hydroxyl (-OH) function. Alternately, several completely synthetic routes yield fatty alcohols which may be structurally identical or similar to the naturally-derived alcohols.

Fatty alcohols generally are primary alcohols conforming to the structure RCH2OH; where the R group varies with each individual alcohol. Those fatty alcohols prepared from naturally occurring fatty acids normally contain an even number of carbon atoms. Fatty alcohols are used as emollients in numerous types of cosmetics. They are valuable as co-emulsifiers and are employed to increase the viscosity of emulsions, shampoos and other products.