Squalene and squalane are two different but closely related chemical compounds that have a number of industrial, medical and cosmetic applications. Squalene, for example, is used in the manufacture of vaccines, while both chemicals are used as ingredients in moisturizing products for the skin and hair. Some people also ingest these chemicals in vitamin pills for their purported antioxidant properties.
Squalene occurs naturally in human skin and in many other plants and animals, although the main source of squalene for most of its history of human use has been shark liver oil. In cosmetics and skin care products, it acts as a moisturizer and emollient, potentially smoothing and softening dry or wrinkled skin. Because the squalene in cosmetics and creams is chemically the same as that which is already present in the skin, it is known as a skin-identical ingredient.
Squalene in its natural form is somewhat chemically unstable, tending to break down through oxidation when exposed to air. Therefore, it is more common in the manufacture of cosmetics and skin care products to convert natural squalene into its close cousin, squalane, through a process called hydrogenation. Squalane has similar moisturizing and emollient properties as squalene, but is more stable and less likely to break down through oxidation.
Sharks in Danger
Sharks’ livers are among the richest natural sources of squalene, and years of harvesting them for use in the cosmetics industry led to severe drops in population in some species, such as the gulper shark and the kitefin shark. Up to one-third of these sharks’ body weight may be contained in their squalene-rich livers. In response to the overfishing, many companies, including L’Oreal and Unilever, have pledged to cease using shark liver-derived squalene in their products.
Alternative Sources of Squalene
Although some companies continue using shark liver oil as the source of their squalene, many others have turned to using plant-derived squalene. Olives provide the largest botanical squalene source, but it can also be derived from wheat germ, rice bran and amaranth seeds. Since the squalene in these botanical sources is less concentrated than in shark livers, relatively more of the source material is needed, but many companies and consumers believe the added expense is justified in order to allow shark populations to rebound.
References and ResourcesCosmetics giants agree to stop using shark oil