Silicones and their use in cosmetics

Surely we have already heard about silicones, with good and bad comments, myths and realities that abound on social media, but what are they for? How do they work? What is their function in Skincare formulations? Are they carcinogenic? We will tell you everything.
 
In 2003, the Cosmetic Ingredient Review expert panel published the final report of its investigation on the following substances: methicone, dimethicone, amino bispropyl dimethicone, aminopropyl dimethicone, among others. This study revealed that, based on the evidence found, silicones are completely safe to use in Skincare formulations. However, the expert panel determined that it was necessary to reopen the investigation due to the increased use of these ingredients in cosmetics.
 
Commonly known as silicones and scientifically called siloxane polymers, methicones are defined by having a methyl group and a hydrogen atom within the polymer backbone, while dimethicones have 2 methyl substituents within the molecule's backbone.
 

The frequency and concentration of silicones in cosmetic formulations have increased significantly. According to data from the Cosmetic Ingredient Review expert panel, the frequency of dimethicone increased from 1,659 reported uses in 1998 to 14,050 reported uses in 2020. The number of reported uses of dimethicone increased from 0 in 1998 to 654 reported uses in 2020. Similarly, the concentration of both substances increased from 30% in 1999 to 85% in 2019. Currently, the permitted concentration in Skincare formulations is approximately 30%.
 
Silicones are used in cosmetic formulations as a sensory active ingredient, providing softness to the touch and upon contact with the skin. Due to the size of the molecule, studies indicate that they are not absorbed by the skin, remaining on the outermost layer. The Cosmetic Ingredient Review expert panel and the FDA determined that, to date, silicones have not shown signs of carcinogenicity in humans, making them a 100% safe product to use in cosmetic formulations.