Colouring Agent/Pigment

CI 45410

Reviewed by Emma · Last updated 14 Aug 2026

A synthetic red dye used primarily to add colour to cosmetic formulations

Best For Skin Types

All

Usage Frequency

Daily

What Is CI 45410?

CI 45410, also known as Phloxine B or D&C Red No. 28, is a synthetic organic dye belonging to the xanthene family. It is a halogenated fluorescein compound used as a cosmetic colorant in skincare, makeup and other topical products. The ingredient serves a purely aesthetic function, imparting red or pink tones to formulations.

As a colorant, CI 45410 does not exert active skincare benefits. Its role is limited to visual appeal and product identification, making it a non-functional ingredient from a therapeutic standpoint.

How It Works

CI 45410 is a synthetic dye molecule that absorbs and reflects light across the visible spectrum to produce red or pink colouration. It does not interact with skin cells or biological pathways; instead, it remains largely on the surface or within the formulation matrix where it is dissolved or suspended.

Clinical Evidence & References

CI 45410 is approved for use in cosmetics across multiple regulatory jurisdictions, including the EU and USA. However, research on this ingredient in skincare contexts is limited. One mechanistic study in cultured keratinocytes examined its photosensitising potential under artificial visible light, suggesting that high concentrations combined with significant light exposure could theoretically generate free radicals. The relevance of this finding to typical cosmetic use at low concentrations remains unclear.

In normal cosmetic formulations at standard concentrations, CI 45410 is generally considered safe for topical use. Most adverse reactions are rare, though individuals with known sensitivities to synthetic dyes should exercise caution.

How to Use

CI 45410 is a passive ingredient requiring no special application technique. Use products containing it according to standard skincare routines. If you have sensitive skin or a history of reactions to synthetic colorants, perform a patch test before broader use. Exposure to intense artificial or natural light immediately after application is not a typical concern with cosmetic concentrations, but sun protection remains important for general skin health.

Safety & Precautions

CI 45410 is approved for cosmetic use and generally well-tolerated. Individuals with sensitivities to synthetic dyes should avoid products containing this colorant or conduct a patch test first.

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