What is cyclopentasiloxane? Cyclopentasiloxane, also known as decamethylcyclopentasiloxane or D5,
is a type of silicone, often used in cosmetics, personal care products, and
certain medical applications. Its main function is as a conditioner, delivery agent, lubricant,
and solvent, providing a silky, smooth feel when applied to the skin or hair. Its low surface
tension allows it to spread easily and fill in fine lines or wrinkles. The substance is volatile,
meaning it evaporates quickly, leaving behind no residue or build-up. Despite these benefits,
there are concerns about its environmental impact. While generally considered safe for
human use, it's non-biodegradable and persistent in the environment,
which has led to regulatory scrutiny and calls for alternatives. It's still
widely used, but manufacturers are exploring more sustainable options.