Steareth-100

Benefits

Softening

What is Steareth-100?

Steareth-100 is a synthetic non-ionic surfactant created by ethoxylating stearyl alcohol with about 100 units of ethylene oxide, forming a long hydrophilic chain attached to a fatty alcohol base typically sourced from plant or animal-derived stearic acid. Commonly used in rinse-off and leave-on cosmetics like shampoos, conditioners, creams, lotions, and toners, it works by lowering surface tension to mix oil and water phases seamlessly. As an emulsifier, it prevents separation in creamy textures; as a cleanser, it lifts away dirt and oils via micelle formation; and as a solubilizer, it disperses fragrances and oils evenly in watery products for clarity and stability. Its high ethoxylation level contributes to mild performance across various formulations.

Comedogenic Rating 0/5 Low risk of clogging pores

EWG Safety Rating 1-3 View on EWG →

PubChem View on PubChem →

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

Delivers softening to skin and hair for smoother feel.

Supports gentle cleansing by removing impurities without stripping.

Aids in creating stable, smooth-textured emulsions.

Who It's For

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

Who May Benefit	Who Should Avoid
People using foaming cleansers and shampoos for daily care.	Those sensitive to polyethylene glycol derivatives.
Individuals with normal to dry skin seeking softening effects.	People preferring products without ethoxylated ingredients.
Users of lotions and toners needing clear, stable formulas.	Individuals concerned about potential trace impurities in surfactants.

Safety Notes

Considered safe for cosmetic use in typical concentrations by regulatory reviews.
Low comedogenic potential, suitable for acne-prone skin.

Frequently Asked Questions about Steareth-100

What does Steareth-100 do in products?

It acts as a surfactant to cleanse, emulsify oils into water, and solubilize fragrances for stable formulas.

Is Steareth-100 safe for sensitive skin?

It is generally mild due to its non-ionic nature and high ethoxylation, with low hazard ratings.

Does it cause breakouts?

No, it has a comedogenic rating of 0, making it unlikely to clog pores.