The ingredient, explained
Ci 17200
A published expert assessment examines cosmetic-use safety.
Ingredient guide
What it is and what it does
Disodium 5-amino-4-hydroxy-3--phenylazo-naphthalene-2‚7-disulphonate
About this ingredient: EU CosIng ingredient registry (via Open Beauty Facts taxonomy) ↗
- Cosmetic colorant
- Adds colour to a product or the surface where it is applied.
Function definitions: European Commission ingredient function definitions (SCCNFP/0299/00, pages 16 to 20) ↗
Registry functions describe possible formulation roles, not results for a finished product. A dictionary entry is not an approval or a safety assessment.
A closer look
What the research shows
Safety assessment
The 2007 opinion supported up to 0.5% Acid Red 33 in non-oxidative hair dyes under its assessed exposure conditions.
What this does not tell us
The assessment identifies impurity concerns and explicitly excludes exposure from other cosmetic uses. It cannot be presented as clearance for skincare products or as current legislation.
Sources for this summary. Published source ↗
Research review checked Oct 1, 2026
Bounded targeted searches for the exact ingredient identity in primary research or final expert assessments, with selected-source verification. Not a systematic review.
Ingredient research is not proof that a product containing this ingredient works.
Read the 1 selected study
Safety assessment
Opinion of the Scientific Committee on Consumer Products on Acid Red 33 (C22) ↗
· 2007
Follow the formula
Products containing this ingredient
From the Serenfold edit. Linked by the ingredient list, without an efficacy ranking.
Names and identifiers
Registry identity
Disodium 5-amino-4-hydroxy-3--phenylazo-naphthalene-2‚7-disulphonate
- INCI name on ingredient lists
- CI 17200
- CAS registry number
- 3567-66-6
- EC number
- 222-656-9
Sources for this ingredient record
- EU CosIng ingredient registry (via Open Beauty Facts taxonomy) ↗ · ODbL 1.0 (Open Beauty Facts database) · Recorded Aug 8, 2026