Black iron oxide (CI 77499) is an inorganic mineral pigment used to provide black to brown coloration in cosmetics such as foundations, mascaras, and tinted sunscreens. It is generally considered safe, stable, and non-reactive in topical formulations.
| Reported effect | How often | Notes |
|---|---|---|
| Allergic contact dermatitis | Rare | Occasional sensitization reported, sometimes linked to nickel or chromium trace impurities rather than the iron oxide itself. |
| Skin irritation | Very rare | Mild irritation is uncommon as iron oxides are largely inert. |
| Pigment-related contact reactions in eye-area products | Rare | Reported in some mascara/eyeliner users, often related to other formulation components. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.
Peer-reviewed papers on this ingredient, via PubMed.