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Is 4-Hydroxyindole vegan?

4-Hydroxyindole

Vegan

4-Hydroxyindole is a synthetic organic compound used as an intermediate in oxidative hair dye formulations.

INCI name 4-Hydroxyindole
CAS number 520-52-5
EC number 219-177-2
CosIng ID 41702
Last reviewed 9 July 2026

Sources

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