What are Azo dyes and its potential health hazard?
Azo dyes are colourants which are an integral part of dyestuff. They have one or several Azo groups (-N=N-) in the molecular structure. It is commonly found in dyed textiles, plastics and leather. The listed aryl amines formed through reduction cleavage from Azo colourants or Azo dyes and are potentially or have proven to be carcinogenic.
What are the related legislations and maximum limit?
Related legislations (non-exhaustive)
European Union: REACH Annex XVII entry 43
China: GB 18401 and GC 20400
Maximum limit (non-exhaustive)
30mg/kg (each or 30 PPM)
20mg/kg (each or 20 PPM)
Case studies of resolved issues
Case 1: Azo compound detected in a black colour, 30s interlocked knitted t-shirt
Case 2: A scarf printed with pigment showed the presence of amines (O-benzidine > 100PPM). The pigment had a direct colour mix-up. By analysing the mixture of inks and base binders, the issue was resolved by appropriate replacement.
Note: The abovementioned content is based on our technical expertise and cannot be considered for any legal dispute.
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