Aromatic amines Azo dyes
o-Tolidine Trypan blue
2,6-Dimethylaniline Ponceau 2R
2,4,5-Trimethylaniline Ponceau 3R
N,N-Dimethyl-p-phylenediamine Methyl Red, Methyl Yellow, Methyl Orange
1-Amino-2-Naphthol Red, Orange I, Orange II, Sudan 1, Sudan IV
1,4-Naphthyldiamine Phenylazo-1-naphthylamine
Sodium Naphthionate Amaranth (Red# 2)
Benzidine Direct Black 38
o-Toluidine Direct Blue 14
Table 2: Examples of potential carcinogenic aromatic amines metabolically produced from azo dyes.