Polymethylsilsesquioxane is a silicone ingredient used in the cosmetic industry.
- Used in many skin care, hair care, and cosmetic formulas, most often as a film former that creates a lubricating, smooth, silky feel and increases the skin or hair’s ability to repel water, according to Marshall Brain, the founder of How Stuff Works.
It is a “spherical, fine particle silicone resin” that is comprised of very small particles, and therefore easily distributed in formulas. In a study done by Grant Inc., a company responsible for cosmetic development, Polymethylsilsesquioxane can be used in particles as small as less than 10 microns, and can impart anti-caking and slip properties to the skin in hair, in addition to its lubrication and water repellent abilities.
- Polydimethylsiloxane is considered to be a 100% safe ingredient by the Cosmetics Database.
Although a large amount of research has connected silicones to cancer and organ failure, it is generally considered to be a hazardous ingredient when injected into the skin or body, but not when applied topically. Many studies find silicones, including Polymethylsilsesquioxane, to be safe when used in the body as well, including a study published in the New England Journal of Medicine, in which after a 14 year study of over 1,000 women with breast implants, a team of researchers and doctors concluded that “we did not find an association between silicone breast implants and connective-tissue diseases, defined according to a variety of standardized criteria, or signs and symptoms of these diseases.”
Source: TruthinAging, https://www.truthinaging.com/ingredients/polymethylsilsesquioxane