Database/Emulsifying Surfactant/PEG-40 Stearate
Mostly petroleum · ISO 16128

Is PEG-40 Stearate natural?

Mostly not. Stearic acid is oleochemical; the dominant mass is the 40-mole petrochemical ethylene oxide chain forming the PEG backbone.

INCI namePEG-40 Stearate
CAS9004-99-3
FormulaC20H40O3 · 328.5 Da
FunctionEmulsifying Surfactant · Cleansing Surfactant
FeedstockStearic acid from vegetable oil or tallow is…

How we scored it

Stearic acid − H2O = 266 natural; 40 EO × 44 = 1762 petrochemical; 266/2028 = 0.13.
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.

Where it comes from

Stearic acid from vegetable oil or tallow is esterified onto a PEG-40 chain built from petrochemical ethylene oxide. The long PEG chain dominates the molecule's mass.

In plain English

An emulsifier that helps water and oil mix in creams and cleansers. Made from stearic acid, a fatty acid from vegetable or animal fat, combined with a long chain of ethylene oxide, a petroleum-derived building block, to make it water-soluble.

CosIng definition: Poly(oxy-1,2-ethanediyl), .alpha.-(1-oxooctadecyl)-.omega.-hydroxy- (40 mol EO average molar ratio)

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 C10-16 Alkyl Glucoside 100% natural origin

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 C12-20 Alkyl Glucoside 100% natural origin

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Structure

2D structure of PEG-40 Stearate

2-hydroxyethyl octadecanoate

PubChem CID 24762 ↗

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. 2PEG-40 Stearate. PubChem CID 24762. National Center for Biotechnology Information. pubchem.ncbi.nlm.nih.gov ↗
  3. 3PEG-40 STEARATE. CosIng — European Commission cosmetic ingredient database. ec.europa.eu/cosing ↗
  4. 4PEG-40 STEARATE. CosIng u2014 European Commission database for information on cosmetic substances and ingredients. https://ec.europa.eu/growth/tools-databases/cosing/search?search=PEG-40%20STEARATE