Overview
ISO 22517:2019 - Leather - Chemical tests - Determination of pesticide residues content specifies a quantitative laboratory method to detect and quantify pesticide residues in leather using gas chromatography–mass spectrometry (GC‑MS). The standard covers extraction, purification, calibration and analytical verification for 24 pesticide compounds (listed in Annex A) and applies to all leather types that could release pesticides.
Key topics and technical requirements
- Analytical principle: Ultrasonic extraction followed by GC‑MS detection and external standard quantification.
- Sample preparation: Follow ISO 2418 for sampling and ISO 4044 for sample cutting/grinding; typical test uses 2.00 g leather processed into 3–5 mm pieces.
- Extraction solvent: n‑hexane : ethyl acetate (1:1 v/v), using 20 ml per extraction; two successive ultrasonic extractions (20 min at 25 °C ± 2 °C) with vortex mixing and centrifugation (5 min at 5 000 r/min).
- Purification: Solid phase extraction (SPE) on graphitized carbon black (Carb) columns; solvent exchange steps with acetonitrile/toluene (3:1) and n‑hexane to protect the GC column.
- Instrumentation & apparatus: Gas chromatograph with mass‑selective detector (electron impact), ultrasonic bath, rotary evaporator (or nitrogen blowdown), centrifuge, SPE system, membrane filtration.
- Calibration & quantification: Calibration solutions in the 10 ng/ml to 1 000 ng/ml range; external standard method. Recovery check prepared from a 1 000 ng/ml mixed standard processed like samples.
- Performance criteria: Recovery rate acceptance 70 %–120 %. Annexes C–E provide retention times, selected ions and example chromatograms; Annex F–G include recovery and precision data.
- Safety: Pesticides may be highly toxic, persistent and potentially carcinogenic - follow chemical safety data sheets and good laboratory practice.
Applications and users
ISO 22517:2019 is intended for:
- Leather testing laboratories and QA/QC units in tanneries
- Product safety and compliance teams assessing chemical residues in finished leather goods (footwear, garments, upholstery)
- Regulatory agencies and import/export testing to ensure consumer safety and environmental compliance
- Research labs working on leather contamination, occupational exposure or pesticide fate in leather processing
Practical uses include routine screening for pesticide contamination, verification of supplier compliance, and investigation of suspected contamination incidents.
Related standards
- ISO 2418 - Leather - Sampling location
- ISO 4044 - Leather - Preparation of chemical test samples
- Document prepared by IULTCS (IUC Commission) in cooperation with CEN (IULTCS/IUC 38)
Keywords: ISO 22517:2019, leather pesticide residues, GC‑MS, leather chemical tests, pesticide testing leather, SPE Carb, extraction protocol, recovery rate.
