Overview
EN ISO 17070:2015 - titled Leather - Chemical tests - Determination of tetrachlorophenol-, trichlorophenol-, dichlorophenol-, monochlorophenol‑isomers and pentachlorophenol content (ISO 17070:2015) - specifies an analytical method for quantifying chlorinated phenols (including PCP and various chloro‑isomers), their salts and esters in leather. Prepared by IULTCS in cooperation with CEN, this standard replaces the 2006 edition and is intended for laboratories performing chemical testing of leather.
Key topics and technical requirements
- Analytes covered: tetrachlorophenols (TeCP), trichlorophenols (TriCP), dichlorophenols (DiCP), monochlorophenols (MoCP) isomers and pentachlorophenol (PCP). (Bromophenols can also be measured by the same method.)
- Principle: steam‑distillation of a prepared leather sample, extraction into n‑hexane, acetylation of chlorinated phenols, and analysis of the resulting chlorinated phenyl acetates by gas chromatography.
- Detection: gas chromatography (GC) using an electron capture detector (ECD) or a mass selective detector (MSD) for separation and quantification.
- Quantification strategy: external calibration corrected by an internal standard - tetrachloroguaiacol (TCG) is specified as the internal standard.
- Sample preparation: sampling and preparation are aligned with ISO 2418 and ISO 4044; typical test is performed on about 1.0 g of leather (as described in the standard).
- Apparatus and reagents: specified equipment includes steam‑distillation apparatus, GC (ECD or MSD), analytical balance and separation vessels; reagents include a defined chlorinated phenol mix, TCG internal standard, n‑hexane, acetic anhydride (for acetylation), potassium carbonate, sulfuric acid and others.
- Results and reporting: the standard gives procedures for expression of results and test reporting, plus informative annexes on chromatographic conditions and method reliability.
Applications and who uses it
- Leather manufacturers and tanneries: quality control to ensure finished products meet chemical safety and regulatory limits for chlorinated phenols.
- Analytical and QA laboratories: routine testing and verification of leather chemical content using GC/ECD or GC/MS methods.
- Regulatory bodies and environmental compliance teams: monitoring PCP and related chlorophenol residues for consumer safety and environmental requirements.
- Product compliance and certification services: assessment for restricted substances lists, ecolabels, and supply‑chain chemical audits.
Related standards
- ISO 2418 - Sampling location for leather and furs
- ISO 4044 - Preparation of chemical test samples (leather)
- ISO 3696 - Water for analytical laboratory use
- ISO 4684 - Determination of volatile matter (leather)
This standard is essential for accurate determination of chlorinated phenols in leather, combining steam‑distillation, chemical derivatization (acetylation) and GC analysis to provide reliable, comparable test results across laboratories. Keywords: EN ISO 17070:2015, leather chemical tests, chlorinated phenols, pentachlorophenol, gas chromatography, steam distillation, TCG internal standard.