Banned amines are aromatic amines, such as benzidine and 4-aminobiphenyl, that are known or suspected to cause cancer. Some azo dyes can split under reducing conditions, including on skin, and release these amines.
Many markets therefore restrict azo dyes that can release them. Labs test for them by chemically splitting the azo bonds in a sample and measuring any listed amines that come out.
The main rule: EU REACH
In the European Union, REACH Annex XVII entry 43 restricts azo dyes that can release any of the aromatic amines in its Appendix 8, a list of 22 amines. Textile and leather articles that may come into direct and prolonged contact with skin or the mouth must not release these amines above 30 mg/kg. Clothing, bedding, towels, footwear, gloves and watch straps are examples.
The rule applies to finished articles placed on the EU market, including imported ones. The importer of the article carries the legal responsibility, so the brand or importer is the party that needs proof. Other markets, including China, Japan and several others, have similar lists, and brand restricted lists often go further.
Confirm the current text and scope with the European Chemicals Agency or your own regulator before you rely on it, since entries are amended from time to time.
How testing works
- For textiles, labs use EN ISO 14362-1, which reduces the azo dyes in the sample and measures released amines by chromatography.
- A separate method, EN ISO 14362-3, covers dyes that release 4-aminoazobenzene, which needs a different procedure.
- For leather, labs use EN ISO 17234 methods.
- For dye powders, makers and labs test the colourant itself, which shows whether the dye can produce a compliant article.
- Results are reported per amine in mg/kg, with the lab's detection limit, and compared with the legal or brand limit.
What this means for a dye buyer
Most mainstream dye makers in India have long since moved away from the restricted amines. Risk remains in three places: cheap blends with unknown components, old stock, and contamination from shared equipment.
- Ask for a recent banned-amine test report on each dye, from an accredited laboratory, naming the exact product and lot.
- Ask the supplier to declare every Colour Index component in a blended dye.
- Check that test reports are current and match the product name on the invoice and the COA.
- Test a dyed fabric now and then, since the article is what the law controls.
- Check the dye against the ZDHC MRSL and your customer's list as well. See whether Indian dyes comply with the ZDHC MRSL.
Next step
We check test reports, confirm they match the lot you buy and arrange independent tests when needed. Read how to read a lab certificate for what a good report shows. To set up testing for your dyes, book a free sourcing review.