Question 1

What does Steareth-100 do in a cosmetic formula?

Accepted Answer

This ingredient is a nonionic emulsifier and solubilizer, mainly used to help oil and water phases mix and to stabilize creams, lotions, and cleansing formulas. Its high ethoxylation level makes it especially useful for dispersing oils, waxy materials, and fragrance components into water-rich systems.

Question 2

Is Steareth-100 clean?

Accepted Answer

From a clean-beauty perspective, this ingredient faces friction because it is ethoxylated and can carry trace processing residues such as 1,4-dioxane or ethylene oxide if not well purified. It is typically low-irritation, but many stricter standards flag the manufacturing route rather than the finished molecule itself.

Question 3

Is Steareth-100 sustainable?

Accepted Answer

This material is made from a fatty alcohol backbone that may come from plant, animal, or synthetic sources, combined with petrochemical-derived ethoxylation. It is expected to have some biodegradability as a fatty alcohol ethoxylate, but the petroleum-linked processing and residue-management requirements weaken its sustainability profile.

Question 4

Is Steareth-100 COSMOS-approved?

Accepted Answer

This ingredient is generally not permitted in COSMOS-natural or COSMOS-organic products because ethoxylation is not an accepted processing route for standard cosmetic ingredients under that framework. Its Green Chemistry fit is limited by petrochemical input, added purification burden, and dependence on residual-contaminant control.

Question 5

How does Steareth-100 work chemically?

Accepted Answer

The molecule is a high-HLB nonionic surfactant built from a long fatty chain attached to a large polyoxyethylene segment, with the number indicating an average of about 100 ethylene oxide units. It is generally stable across a broad pH range and is used at low formulation percentages for emulsification, solubilization, and stabilization, often alongside lower-HLB emulsifiers or fatty alcohols.