Use of surgical masks for sampling in the determination of volatile organic compounds

In the SARS-COV-2 pandemic the use of masks has been one of the most efficient and extended practice to reduce the infection rate by virus propagation. Due to the ease of use and reduced cost of surgical masks, we have evaluated them for sampling exhaled breath by retention of volatile organic compounds (VOCs). A method based on headspace–solid-phase microextraction coupled to gas chromatography–mass spectrometry (HS–SPME–GC–MS) was developed for the determination of retained compounds in surgical masks used by volunteers during the period recommended by manufacturers. Analysis of results revealed that masks can retain VOCs from exhaled air, but also from the environment by exposition of users. We tentatively identified 63 compounds associated to 10 different chemical families and characterized the intra-individual (from 18 to 160%) and inter-individuals (from 32 to 260%) variability by analysis of masks collected for six days. Finally, we identified markers associated with the intake of products such as coffee and beer, chewing gum, smoking or use of toohpaste. All this suggests that surgical masks could be used as a simple and inexpensive sampling system for the analysis of volatile organic compounds.