"Blue" typically refers to synthetic blue colorants (such as Blue 1/CI 42090 or Blue 2/CI 73015) used to impart color to cosmetic and skincare formulations. It serves an aesthetic role and has no therapeutic skin benefit.
| Reported effect | How often | Notes |
|---|---|---|
| Skin irritation | Uncommon | Mild redness or stinging possible in sensitive individuals. |
| Allergic contact dermatitis | Rare | Sensitization to synthetic dyes has been documented in patch-test studies. |
| Temporary skin staining | Uncommon | Transient discoloration that washes off. |
| Eye irritation | Rare | If product contacts the eyes, depending on the specific dye approval status. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.
Peer-reviewed papers on this ingredient, via PubMed.