Overview
EN ISO 17072-1:2019 - Leather: Chemical determination of metal content - Part 1: Extractable metals specifies a standardized laboratory method for measuring extractable metals in leather. The method uses extraction with an acid artificial-perspiration solution (37 ± 2 °C for 4 h ± 5 min), followed by filtration, acidification and instrumental analysis by ICP-OES, ICP-MS, AAS or atomic fluorescence spectrometry (SFA). Results are reported on the dry matter of the leather. The method is not compound‑specific or oxidation‑state specific and is particularly suited for measuring extractable chromium from chromium‑tanned leathers.
Key topics and requirements
- Scope and applicability: Determination of a wide range of extractable metals in leather (e.g., Al, As, Ba, Ca, Cd, Cr, Co, Cu, Fe, Hg, Mn, Ni, Pb, Zn, and others as listed in the standard).
- Extraction procedure: Use of an acid artificial‑perspiration solution at controlled temperature and agitation for a fixed extraction time (37 ± 2 °C, 4 h ± 5 min).
- Analytical techniques: Quantification using ICP‑OES, ICP‑MS, flame/graphite‑furnace AAS (with hydride generation where appropriate) or SFA for mercury.
- Sample preparation & reporting: Conformance with sampling and sample prep (references such as ISO 4044), filtration (0.45 µm suggested), acidification of extracts and expression of results per dry matter.
- Apparatus & reagents: Requirements include trace‑metal clean glassware, ovens, balances, membrane filters, water baths/shakers, certified reference solutions and grade‑specific reagents; safety warnings for strong acids are highlighted.
- Quality considerations: Use of analytical‑grade gases and instrument modules (hydride generator), calibration with element stock solutions and interlaboratory quantification limits (Annex A).
Applications and users
- Who uses it: Leather manufacturers, tanneries, independent testing laboratories, quality assurance teams, product safety and compliance officers, and research labs focused on leather chemistry.
- Practical uses:
- Routine product testing to assess extractable metal levels from leather articles.
- Safety and compliance testing for consumer products (e.g., footwear, garments, upholstery).
- Verification of tanning processes (especially chromium tanning) and supplier quality control.
- Supporting regulatory or certification requirements through standardized, comparable test results.
Related standards
Relevant normative references within EN ISO 17072-1:2019 include:
Using EN ISO 17072-1:2019 ensures reproducible, traceable measurements of extractable metals in leather and supports product safety, quality control and comparability across laboratories.