Science
Mechanism of Action
For skin, there is no identified beneficial mechanism of action for HC RED NO. 9. Its presence on the skin primarily involves the potential for staining, and may introduce risks of irritation or sensitization through direct contact.
Research
Clinical Evidence
Insufficient-data confidenceN/A
Transparency
Dusting Analysis
This ingredient is not a skincare active and is primarily used as a hair dye, therefore, the concept of 'dusting' does not apply in a skincare context.
The Formula
Formulation
Stability
Specific optimal pH for HC RED NO. 9's stability is not detailed. However, related hair dye formulations commonly operate in an alkaline environment (e.g., pH 8-11) to enhance dye penetration. This direct dye typically exists in aqueous alcoholic solutions.
Conflicts
- N-nitrosating agents (potential for nitrosamine formation, inferred from related HC Red dyes)
Safety
Safety Profile
The Cosmetic Ingredient Review (CIR) Expert Panel has not assessed HC RED NO. 9 for safety. The Scientific Committee on Cosmetic Products and Non-Food Products (SCCNFP) previously indicated that its use could not be considered safe without adequate safety data, as no dossier was submitted. In the US, the FDA classifies it as a 'coal-tar hair dye', exempting it from pre-market approval but mandating a caution statement and patch test instructions on product labels due to potential risks.
Your Skin
Skin Compatibility
Our Assessment
Verdict
HC RED NO. 9 offers no reported benefits for skin, carries potential risks of irritation and sensitization, and lacks comprehensive safety data for dermal application, making it unsuitable for precision skincare formulations.
Related
Similar Ingredients
Finding similar ingredients…