Database/Emulsifying Surfactant/PEG-100 Castor Oil
Mostly petroleum · ISO 16128

Is PEG-100 Castor Oil natural?

Mostly not. Natural castor-oil triglyceride core heavily diluted by a long petrochemical polyethylene-glycol (100 EO) chain.

INCI namePEG-100 Castor Oil
CAS61791-12-6
FunctionEmulsifying Surfactant · Cleansing Surfactant
FeedstockMade by ethoxylating castor oil (Ricinus communis seed…

How we scored it

Castor oil triglyceride (~934 Da, natural) + 100 EO × 44 Da (4405 Da, petrochemical) = 5339 Da → 934/5339 = 0.17.
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

Made by ethoxylating castor oil (Ricinus communis seed oil) with about 100 moles of ethylene oxide. No natural-only alternative route.

In plain English

Castor oil heavily modified with a long synthetic polyethylene glycol chain, used as an emulsifier and cleanser in cosmetics and washes.

CosIng definition: Castor oil, ethoxylated (100 mol EO average molar ratio)

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. 2PEG-100 CASTOR OIL. CosIng — European Commission cosmetic ingredient database. ec.europa.eu/cosing ↗
  3. 3PEG-100 CASTOR OIL. CosIng u2014 European Commission database for information on cosmetic substances and ingredients. https://ec.europa.eu/growth/tools-databases/cosing/search?search=PEG-100%20CASTOR%20OIL