Determination of Dimethylfumarate in Leather and Footwear by Solid-Phase micro Extraction and Gas Chromatography-Mass Spectrometry

Abstract

In the last two years, Europe has experienced a rise in skin allery and dermatitis due to goods and Asian provenance that have been treacted with dimethylfumarate (DMFU). Accordingly,laboratories in the leather and foodwear sectors have been obliged to develop analytical methods to determine the presence of this substance given de absence of an official method. The ban on DMFU as laid down in Decision 2009/251 of the European Union establishes a maximun concentration of DMFU in products of 0.1 mg/Kg. A simple nom-destructive rapid method based on manual headspace solid-phase micro extraction (HS-SPME) and gas cromatography-mass spectrometry (GC-MS)is proposed to detect DMFU in leather and footwear. Thereafter, the samples which DMFU is detected are analysed by solid-liquid extraction (SLE) with acetone after which DMFU is quantitatively determined by GC-MS. The quantitative method in validated in terms of linearity, precision, sensivity and recovery; demostrating its reliability. Quantification of this performed used naphthalene-D8 as internal standard. The detection limits are 0.005 mg/Kg and 0.03 mg/Kg for the HS-SPME-GC-MS and SLE-GC-MS methods, respectively. Given that these limits are bellow the maximun limit of 0.1 mg/Kg imposed by the European Union, the proposed methods are suitable for determining DMFU content in real samples.