CI 42090/Blue

TL;DR. This ingredient is a synthetic colorant used to tint aqueous personal care products and standardize product appearance at very low concentrations.

What does CI 42090/Blue do in a cosmetic formula?

This ingredient is a synthetic colorant used to tint aqueous personal care products and standardize product appearance at very low concentrations.

Is CI 42090/Blue clean?

From a clean-beauty perspective, it is a frequent point of friction because many standards restrict synthetic colorants and require tight purity controls. It is generally used at trace levels, but colorant sensitivity can occur in a small subset of users.

Is CI 42090/Blue sustainable?

It is made by chemical synthesis from non-renewable aromatic feedstocks, so it is not a strong match for renewable-sourcing goals. Its environmental profile depends on dye-manufacturing controls and wastewater capture, and ready biodegradability is not its main strength.

Is CI 42090/Blue COSMOS-approved?

It is not permitted in COSMOS-natural or COSMOS-organic products because the standard favors approved nature-derived or mineral colorants over this class of synthetic dye. Its Green Chemistry fit is limited by non-renewable feedstocks and modest biodegradability, although high color strength keeps use levels very low.

How does CI 42090/Blue work chemically?

The molecule is an anionic, sulfonated triarylmethane colorant designed for high water solubility and strong tinting in water-based systems. It is typically used at trace levels, often well below 0.1%, and can be affected by strong oxidizers, reducing agents, and cationic ingredients that may shift shade or reduce solubility.

Last updated 2026-05-14