Database/Emulsifying Surfactant/Polysorbate 40
Mostly petroleum · ISO 16128

Is Polysorbate 40 natural?

Mostly not. Natural sorbitan (from sorbitol) esterified with palm-derived palmitic acid; the ~20 mol petrochemical ethylene oxide chain dilutes the natural fraction.

INCI namePolysorbate 40
CAS9005-66-7
FunctionEmulsifying Surfactant · Cleansing Surfactant
FeedstockMade by esterifying sorbitol-derived sorbitan with palmitic acid…

How we scored it

Sorbitan monopalmitate (natural: sorbitan 164 + palmitic acid 256 minus H2O = 403 Da) + 20 mol EO (881 Da, petrochemical). 403/1284 = 0.31.
What counts. ISO 16128-2 scores the atoms that remain in the final ingredient. Reagents, solvents, catalysts and protecting groups used during manufacture leave no mass behind and are not counted.

How it’s made

Acid-catalysed ring closure of sorbitol (intramolecular SN2). Sorbitan is the ring at the core of every sorbitan ester and polysorbate. Each curved arrow moves one electron pair, and the film ends on the scores for the whole family.

Where it comes from

Made by esterifying sorbitol-derived sorbitan with palmitic acid (typically palm or vegetable oil derived), then ethoxylating with ~20 mol petrochemical ethylene oxide. No alternative commercial route.

In plain English

An emulsifier that blends oil and water in creams and cleansers. Made from plant-derived sorbitol and palm fatty acid, reacted with synthetic ethylene oxide to make it water-soluble.

CosIng definition: Sorbitan, monohexadecanoate, poly(oxy-1,2-ethanediyl) derivs.

Natural alternatives with the same function

Arachidic Acid 100% natural origin

A waxy fatty acid from peanut and other vegetable oils, used to thicken formulas and give creams and…

 Arachidyl Glucoside 100% natural origin

A gentle, sugar-based emulsifier used in creams and lotions to stabilize formulas without harsh surfactants. It's made from…

 Behenic Acid 100% natural origin

A long-chain fatty acid from vegetable oil, used to thicken and stabilise creams and conditioners. It is extracted…

 C10-16 Alkyl Glucoside 100% natural origin

A mild, sugar-based cleansing and emulsifying surfactant made by combining plant-derived fatty alcohols (coconut/palm) with glucose from starch.…

 C12-20 Alkyl Glucoside 100% natural origin

A mild, sugar-based cleansing ingredient made from coconut or palm fatty alcohols and glucose; helps cleanse skin and…

 C18-36 Acid 100% natural origin

A blend of long-chain plant fatty acids used as a mild cleanser and thickener, giving body and a…

References

  1. 1ISO 16128-1:2016 and ISO 16128-2:2017 — Guidelines on technical definitions and criteria for natural and organic cosmetic ingredients and products. ISO, Geneva.
  2. 2POLYSORBATE 40. CosIng — European Commission cosmetic ingredient database. ec.europa.eu/cosing ↗
  3. 3POLYSORBATE 40. CosIng u2014 European Commission database for information on cosmetic substances and ingredients. https://ec.europa.eu/growth/tools-databases/cosing/search?search=POLYSORBATE%2040