PEG-40 Castor Oil

PEG / Ethoxylated

Concerns

Malassezia Feeding

What is PEG-40 Castor Oil?

PEG-40 Castor Oil derives from castor oil, a vegetable oil extracted from Ricinus communis seeds, chemically modified by adding about 40 units of ethylene oxide to create a polyoxyethylene chain. This ethoxylation process transforms the hydrophobic castor oil triglycerides, mainly ricinoleic acid esters, into a water-soluble, non-ionic compound. Commonly found in rinse-off formulations like shampoos, body washes, and makeup removers, it functions by reducing surface tension between oil and water phases. This enables effective emulsification of oils into watery bases and solubilization of lipophilic ingredients such as fragrances or essential oils, resulting in stable, clear solutions. In surfactant systems, it aids micelle formation to lift away residues, supporting gentle yet efficient cleansing without stripping natural moisture barriers excessively.

Comedogenic Rating 0/5 Low risk of clogging pores

EWG Safety Rating 2-4 View on EWG →

Roles in Formulation

This ingredient serves the following purposes in cosmetic formulations:

Surfactant

Lowers surface tension to enable cleansing, emulsifying, and foaming; central to shampoos, body washes, and many emulsions and micellar systems.

Cleansing agent

Removes dirt, oil, and impurities by lowering surface tension and forming micelles, enabling soils to be lifted and rinsed away from skin, hair, or teeth.

Solubilizing agent

Helps incorporate oils and fragrance into water-based formulas by forming micro-solutions, enabling clear sprays, toners, and micellar products.

Benefits

Enhances cleansing by forming micelles that trap and remove oils and dirt.

Solubilizes fragrances and oils for clear, stable water-based formulas.

Supports emulsion stability in shampoos and washes for better texture.

Who It's For

A quick guide for who this ingredient may suit (and who should be cautious).

Who May Benefit	Who Should Avoid
Users of daily cleansers needing effective oil removal.	Those prone to malassezia-related skin issues like fungal acne.
Individuals with normal to oily skin seeking foaming products.	People with sensitivity to ethoxylated ingredients.
People preferring scented sprays or toners with solubilized actives.	Individuals avoiding PEG compounds due to contamination concerns.

Safety Notes

Rated low to moderate hazard by EWG, with safe use affirmed by cosmetic safety reviews.
Potential for trace impurities like ethylene oxide, addressed through purification processes.

Frequently Asked Questions about PEG-40 Castor Oil

What is PEG-40 Castor Oil made from?

It is castor oil reacted with ethylene oxide to add hydrophilic chains, making it soluble in water.

Is it suitable for sensitive skin?

Generally low irritation, but those sensitive to PEGs or with fungal acne concerns may want to avoid it.

What products commonly contain it?

Found in shampoos, body washes, and micellar waters for cleansing and solubilizing.