The science of bio-based alkanes in cosmetics

ABSTRACT In recent years, bio-based alkanes obtained from vegetable oils or sugar, respectively by processes of conventional chemistry and by synthetic biology implemented from genetically modified microorganisms, have appeared on the market. An examination of the production yields and the results of lifecycle analyses highlight the great superiority of conventional chemistry compared to synthetic biology, which ultimately proves to be of low productivity and high environmental impact, far from being in phase with the societal and environmental requirements of the cosmetics industry.

Alkanes of fossil origin have been used in cosmetic products for many years. Indeed, many skin care, hair care or even make-up products contain isododecane, isohexadecane and purified petroleum cuts (e.g. Isopar isoparaffins).1 These petrochemical alkanes are multifunctional compounds with interesting physical and sensory properties: emollient, moisturizing properties, non-greasy and silky feel, excellent skin tolerance, great chemical stability.2 In addition, their price is extremely competitive.

However, they also have their drawbacks. They are derived from non-renewable fossil raw materials, generating greenhouse gases as they are obtained by hydrocracking petroleum. On the other hand, they are far from being totally biodegradable, leading to pollution of water, air and soil. Some of these alkanes also have a synthetic hydrocarbon odour that must be masked in cosmetic formulations by using masking and odorant substances, which make the formulations more complex and can lead to skin tolerance problems.