Is Tropaeolin OOO2 vegan?

Tropaeolin OOO2

Vegan

Tropaeolin OOO2 (Orange II) is a synthetic azo dye belonging to the acid dye group, used as a pH indicator. It is part of the tropaeolin series of dyes, named after the botanical name Tropaeolum for nasturtiums. It is produced entirely from synthetic precursors.

Also known as 2-Naphthol Orange, 2-napththol orange, Acid Orange 7, Orange II
CAS number 633-96-5
CI number CI 15510
Last reviewed 3 June 2026

Sources

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