Overview
EN ISO 17234-1:2024 - Leather - Chemical tests for the determination of certain azo colourants in dyed leathers - Part 1: Determination of certain aromatic amines derived from azo colourants - specifies a laboratory method to detect and quantify aromatic amines released by reductive cleavage of azo colourants in dyed leather. Published December 2024 and adopted by CEN, it supersedes EN ISO 17234-1:2020 and aligns with regulatory lists (e.g., EU Regulation 1907/2006 Annex XVII, Appendix 8 and GB 20400-2006).
Key topics and technical requirements
- Scope: Applies to dyed leathers where azo dyes may release regulated aromatic amines.
- Analytical principle: Reductive cleavage of azo bonds to liberate aromatic amines followed by extraction and chromatographic determination.
- Main procedural steps:
- Sample preparation and degreasing
- Reductive cleavage of azo groups
- Liquid–liquid extraction of liberated amines (alternate procedure without diatomaceous earth included)
- Chromatographic analysis, system checks and calibration
- Calculation, method reliability assessment and test reporting
- Apparatus & reagents: Defined in the standard (referenced normative standards for sample prep and laboratory water quality).
- Performance & validation: Calibration, evaluation, and reliability data are specified; informative annexes provide chromatographic guidance and interpretation aids.
- Normative annexes: Annexes E and F (added in this edition) provide normative methods for determination of certain aromatic amines and free aromatic amines.
Applications and users
- Who uses it:
- Leather testing laboratories and chemical analysts
- Tanneries and leather manufacturers performing internal quality control
- Compliance and product-safety teams verifying conformity with REACH and national restrictions
- Importers, retailers and certification bodies assessing chemical safety of leather goods
- Practical uses:
- Regulatory compliance (REACH / national bans on certain aromatic amines)
- Supplier and incoming material testing to prevent contaminated batches
- Safety risk assessment for consumer products (footwear, garments, upholstery)
- Forensic or investigative chemistry where azo-dye cleavage products are of concern
Related standards
Keywords: EN ISO 17234-1:2024, leather chemical tests, azo colourants, aromatic amines, REACH compliance, dyed leathers, reductive cleavage, chromatographic analysis.