Ponceau is a mono azo dye and is primarily composed of trisodium 2 hydroxy-1-Naphtylene-6,8-Disulfonate.
| No. | Molecular Description | Composition |
| 1. | Total colour/Assay, percent by Mass, min. | 80 |
| 2. | Water-insoluble matter, percent by mass, Max. | 0.2 |
| 3. | Combined ether extracts, percent by mass, Max. | 0.2 |
| 4. | Subsidiary dyes, percent by mass, Max. | 1 |
| 5. | Dye intermediates, percent by mass, max. 1-naphthylamine-4-sulfonic acid 2-naphthol-6,8-di-sulfonic acid |
0.5 |
| 6. | Unsulfonated primary aromatic amine (calculated as aniline) percent by mass, max. | 0.01 |
| 7. | Lead, mg/kg, Max. | 10 |
| 8. | Arsenic, mg/kg, Max. | 3 |
| 9. | Heavy metals, (as pb) mg/kg, max | 40 |
| Mercury, mg/kg, Max. | 1 | |
| Cadmium, mg/kg, Max | 1 |