Colouring Agent/Pigment

CI 15510

Reviewed by Rosie · Last updated 14 Aug 2026

A synthetic red colourant used to add visual appeal to skincare formulations

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What Is CI 15510?

CI 15510, also known as Amaranth or FD&C Red No. 2, is a synthetic azo dye approved for use in cosmetics and personal care products. It is a water-soluble colorant that imparts a red to pink hue to formulations. In skincare products, it serves purely an aesthetic function—colouring the product rather than delivering active skincare benefits.

This ingredient is regulated by cosmetic authorities in most regions and appears in a small fraction of skincare products, typically in concentrations below 1%. Its role is cosmetic rather than therapeutic.

How It Works

CI 15510 is a synthetic colorant that dissolves in water-based formulations and imparts colour through light absorption. It does not penetrate the skin or interact with skin cells in a meaningful way. Its function is visual only—it colours the product itself rather than affecting skin physiology or appearance.

Clinical Evidence & References

There is no clinical evidence that CI 15510 delivers skin benefits, as it is not designed to do so. It is a permitted cosmetic colorant with a long history of safe use in regulated markets. Some older studies raised safety concerns about synthetic azo dyes, but CI 15510 has been reassessed and approved for continued use in cosmetics under current guidelines.

How to Use

No special usage instructions apply; the ingredient functions passively within the formulation. Its presence has no impact on how the product should be applied or how often it is used.

Safety & Precautions

CI 15510 is generally considered safe for topical cosmetic use at approved concentrations. It is not intended to be ingested. Those with sensitivities to synthetic dyes may prefer uncoloured alternatives.

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