3,3'-Dimethoxybenzidine (ortho-Dianisidine) and its salts

6

Avoid

CAS Number: 119-90-4

About 3,3'-Dimethoxybenzidine (ortho-Dianisidine) and its salts

A cosmetic ingredient. Raw material is classified as a suspected carcinogen. Exercise caution due to limited available safety data.

Detailed Analysis

3,3'-Dimethoxybenzidine (CAS 119-90-4), also known as ortho-dianisidine, is an aromatic amine that has been used as an intermediate in azo dye synthesis. EU Regulation 1223/2009 Annex II prohibits the use of this compound and its salts in cosmetic products. The compound and its metabolites (including 3,3'-dimethoxybenzidine itself) have been associated with bladder cancer in occupationally exposed workers. It is classified as a Group 1 carcinogen by IARC and carries hazard statements H302 (harmful if swallowed), H350 (may cause cancer), H341 (suspected of causing genetic defects), and H372 (causes damage to organs through prolonged or repeated exposure).

Known Concerns

  • ⚠ EU Annex II banned - confirmed human carcinogen
  • ⚠ Bladder cancer risk from urinary tract exposure
  • ⚠ Confirmed mutagen (metabolites)
  • ⚠ Organ toxicity through repeated exposure (H372)

Safety Score

6

Avoid

Based on EU regulatory data, published safety research, and ingredient function analysis.

References

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EU CosIng Database

European Commission cosmetic ingredient registry

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This information is for educational purposes only and does not constitute medical advice. Always consult a healthcare professional for skin concerns or allergies.