Overview
ISO 16186:2021 specifies a validated analytical method for the determination of dimethyl fumarate (DMFU) in footwear and footwear components (metal parts excluded). The method uses gas chromatography coupled to single‑quadrupole or tandem‑quadrupole mass spectrometry (GC‑MS / GC‑MS/MS) after solvent extraction. The standard supports regulatory compliance and product safety by providing a reproducible procedure to quantify DMFU - a potent skin sensitizer - in materials such as leather, textiles and polymer components. Note: the introduction references the EU market restriction at 0.1 mg/kg.
Key topics and technical requirements
- Scope: Applicable to all footwear materials except metal parts; two sample workflows for simple and complex matrices.
- Extraction: Sample (typically 1.0 g) is extracted with acetone in an ultrasonic bath at about 60 °C for 60 minutes (see safety notes and Annex C regarding solvent precautions).
- Internal standard: Uses deuterated dimethyl fumarate (d‑DMFU) for quantification.
- Analytical techniques: Analysis by GC‑MS or GC‑MS/MS with chromatographic separation to avoid interference from dimethyl maleate (DMMA).
- Clean‑up (complex matrices): Concentration and clean‑up on activated magnesium silicate (Florisil®) cartridges using n‑hexane/acetone (80/20 v/v), followed by filtration through PTFE 0.45 µm.
- Calibration and quantification: At least three calibration solutions (DMFU + DMMA + internal standard) and calculation of results according to Clause 9; final results reported in mg/kg.
- Limit of quantification (LOQ): Can be lowered by concentrating the extract (see Annex D for reliability data).
- Safety and reporting: Standard contains warnings about hazardous materials and specifies test‑report content (reference to ISO 16186:2021, sample ID, procedure used, result, deviations).
Applications and users
ISO 16186:2021 is intended for:
- Footwear manufacturers and component suppliers performing incoming/outgoing quality control.
- Accredited testing laboratories performing regulatory compliance testing.
- Regulatory bodies and customs laboratories enforcing chemical restrictions (e.g., EU limits).
- Product safety and R&D teams assessing material formulations and alternative processing.
Practical use cases include screening leather and textile components for DMFU contamination, validating supplier claims, and supporting recall investigations.
Related standards
- ISO/TS 16186:2012 (previous edition replaced by this first edition of ISO 16186:2021)
- ISO 4787 (laboratory glassware - volumetric instruments), cited in normative references
Keywords: ISO 16186:2021, dimethyl fumarate, DMFU, footwear testing, GC‑MS, GC‑MS/MS, Florisil clean‑up, acetone extraction, limit of quantification, chemical safety, regulatory compliance.
Open preview (PDF)Footwear — Critical substances potentially present in footwear and footwear components — Determination of dimethyl fumarate (DMFU)
