What it is
Polysorbate 80 is a nonionic surfactant and emulsifier widely used in pharmaceuticals, foods, and cosmetics. It is built from a polyethoxylated sorbitan backbone esterified with oleic acid, giving it a water-loving polyether portion and an oil-loving fatty acid portion that lets it bridge oil and water phases. In formulas it stabilizes emulsions and helps disperse small amounts of oil-soluble materials, such as fragrance or oily actives, into watery bases. The trailing number 80 designates the oleic acid component of the molecule.
Safety & warnings
Polysorbate 80 is regarded as generally well tolerated on skin; cosmetic ingredient references list it as non-irritating and non-comedogenic in typical use. Because it is a surfactant, very high levels can theoretically contribute to mild stripping or sensitivity in some people, but at the small percentages used to emulsify or solubilize it is considered low-risk for most users, including those with oily or breakout-prone skin.
Origin & sourcing
Polysorbate 80 is a synthetic, semi-synthetic ingredient. It is made by reacting sorbitol (a sugar alcohol) to form sorbitan, ethoxylating it with ethylene oxide to add the hydrophilic polyether chains, and esterifying the result with oleic acid, a fatty acid that can be sourced from plant oils. The proportions of these starting materials define the polysorbate grade.
Questions everyone asks
Is Polysorbate 80 the same as Tween 80?
Yes. Tween 80 is a common brand and trade name for Polysorbate 80, also known by the chemical name polyoxyethylene (20) sorbitan monooleate.
What does Polysorbate 80 do in a sunscreen?
It works as an emulsifier and solubilizer, helping the oil and water portions of the formula stay mixed and helping disperse oily ingredients evenly so the product feels uniform.
Will Polysorbate 80 clog pores?
Cosmetic ingredient references rate it as non-comedogenic, so it is generally considered unlikely to clog pores at the levels used in skincare.