Chasing Pollutants Concerning Public Health: From Food to Smoke ^†

Sample preparation is the key step in determining low concentrations of pollutants from food, biological, plant, industrial, and environmental matrices. Solid-phase microextraction (SPME) is a solvent-free, cost-effective, robust, and high-throughput sample preparation technique [1] usually coupled with gas chromatography (GC). It is especially versatile for sampling volatile organic compounds (VOCs) not only present in the analysis of wine bouquet or cheese aromas [2], but also in cigarette smoke [3], or in the identification of microplastics (MPs) [4]. The sorption of VOCs on the SPME fibre in the headspace (HS) of the sample depends on numerous parameters: the type of fibre, the extraction time, and the temperature. Mixed-polarity phase SPME fibres (DVB/CAR/PDMS; Supelco, Bellefonte, PA, USA) were used in all analyses, from Nanos cheese to MP identification to cigarette smoke. The HS-SPME method enabled the VOCs’ profile study of Nanos cheese. The evolved cheese aroma profiles were affected by cheesemaking parameters: the amount of starter culture, ripening temperature, and media, and were independent of the geographical origin of raw milk as well as the location of ripening [2]. Further, by employing the HS-SPME-GC–MS method, identification of the five most common polymer types (PVC, PS, PET, PP, and PE) of MPs was possible. The well-controlled melting process, which generates characteristic compounds of each polymer, enabled the classification of MPs from real mixtures. Studying other VOCs concerning public health also included HS-SPME of flavours in tobacco products [classic cigarettes (CCs), electronic cigarettes (ECs), and heat-no-burn products (HNB)]. Flavours are the most common reason for promoting smoking initiation and duration, and they make smoking cessation more difficult among adolescents. However, the lack of simple smoke/aerosol/vapour (S/A/V) analyses for comparison of CCs, ECs, and HNB makes legislation or prohibition of such products impossible. It would be of general interest if a simple, standardised method existed.