Per- and poly-fluoroalkyl substances (PFAS) are applied to food packaging and other materials to provide fat, fire, and/or water resistance properties. Emissions of PFAS from industrial wastes lead to environmental contamination. These compounds are known as "forever chemicals" due to their stability and persistence. PFAS are expected to have carcinogenic and reprotoxic effects on humans. Every day, PFAS may come into contact with people through the environment, food, and water. In summer 2022, the European Union moved forward in the fight against PFAS contamination in food and feed [1-3]. There is a need to develop increasingly sensitive and accurate analytical methods to investigate contamination levels of PFAS in the food chain to control food quality, preserve the product's safety, and prevent economic losses. The metrological approach is of paramount importance due to the lack of harmonisation and traceable methods. The aim of this study is to use a metrological approach to assess the level of PFAS contamination in rice and maize samples. The analytical method is developed on UHPLC-HRMS performing the isotopic dilution approach. All the standards were CRMs. The samples were extracted, purified and directly injected into the HPLC system. The calibration curves for the targeted method were built considering the whole budget of uncertainties. The untargeted (screening) approach was performed matching results of FullMS experiment with database and dedicated software.The method has been demonstrated to provide robust, reproducible, and reliable results.The outcomes of the targeted analysis obtained due to the linear regression resulted in a calculated average LOQ for the 21 PFAS and the 4 regulated by EFSA of 30 ng/kg and 10 ng/kg, respectively. The screening approach allowed the identification of all the new synthetical PFAS contaminants (GenX and similar) in the samples. The sensitivity, recovery and selectivity parameters obtained showed that the validated method is suitable to assess the levels of contamination of PFAS in this kind of matrix. The method was tested with proficiency testing samples from EURL-POPs. The metrological approach will be performed with real samples to assess the level of contamination in northwest Italy.

In the food industry, titanium dioxide (E171) is used as a coloring agent, opacifier or flavor carrier in foodstuffs or as a clarifying agent in drinks. In some common foods, a fraction (5 to 50 %) of this additive has been found with a size lower than 100 nm (1). This fraction, able to cross physiological barriers and then to be accumulated in systemic organs, may cause problems with the digestive system. Thus, EFSA has concluded this additive cannot be considered safe (2). As the toxicological effects depend mainly on the size and concentration of TiO2particles, the determination of these parameters is crucial to assess the level of dietary exposure and establish appropriate risk management procedures. This study also highlighted the lack of harmonization between techniques for TiO2 nanoparticles (NPs) characterization as well as the need to develop sample preparation procedures. During the last decade, ICP-MS used in single particle mode (spICP-MS) was strongly developed and appears today as one of the most promising techniques for routine quality control of inorganic NPs in foods. Moreover, the high sensitivity and selectivity of spICP-MS allow to face the analytical challenges of food matrices.This work was focused on the optimization of sample preparation procedures allowing a quantitative extraction of TiO2 NPs from food sauces. Different extraction reagents (water, surfactants, acids, TMAH, enzymes) were studied and the potential of the spICP-MS technique was evaluated for the size characterization and quantification of NPs. The method was optimized using a white sauce and its corresponding E171 additive. The highest extracted amount of TiO2 particles was obtained using TMAH with similar TiO2 particle size distributions in the two samples showing no matrix effects during analysis. After validation, the method was applied to several sauces from the European market. Concentration values in the (0.6 6) g(TiO2)/kg range were obtained for the E171 labelled sauces with median diameters in the range 206 280 nm and a percentage of TiO2 NPs (< 100 nm) between 2 and 12 %. No titanium was detected in sauces purchased in the French market which complies with current regulations.

Titanium dioxide (TiO2) is applied in food as a white pigment and listed as food additive E 171. EFSA's opinion [1] states that it is not certain that its use in food is safe because it may be genotoxic. Hence, the European Commission no longer allows E 171 [2]. Consequently, authorities need analytical methods to control the absence of E 171. Because most Ti occurs in food as TiO2, screening can be realized by analyzing the total Ti content as a measure (proxy) for TiO2. This study examined whether the concentrations of total Ti are (much) larger in food products containing E 171 than in products without E 171. The rationale behind this is that the refractive properties of E 171 are only useful at relatively high amounts, requiring the addition of E 171. Challenges related to the measurement of Ti by ICP-OES in food are mainly related to sample preparation: TiO2 is practically insoluble and requires a mixture of concentrated hydrofluoric, sulfuric, and/or other acids for dissolution. However, the typically applied hydrofluoric acid solution is an ultrahazardous chemical that should be avoided for safety reasons. Hence, a digestion method using microwave digestion at 220°C in a mixture of nitric acid and sulphuric acid was optimized and evaluated for the analysis of total Ti in a variety of food samples collected before and after the ban of E 171. The measured concentrations of total Ti ranged from < 2 mg/kg to 13305 mg/kg, and from < 2 mg/kg to 26 mg/kg for foods known to contain E 171, and without added E 171, respectively. Cocoa products contained the highest natural Ti levels up to 25.5 mg/kg. When comparing four identical food items (brand, name, package) before and after the ban, the difference in total Ti concentration ranged up to 3 orders of magnitudes. Titanium concentrations above 50 mg/kg were only detected in food containing E 171. In the next phase, these analytical results will be compared with Ti concentrations measured by other analytical techniques (e.g. Raman, XRF). These results guide competent authorities in setting cut-off values when screening food products for the presence of the banned E 171 and give insights on the methods which are fit for purpose for such control.

The olive tree is an evergreen tree cultivated for thousands of years throughout the Mediterranean basin, which represents the largest international olive growing area. The European Union holds the record in terms of olives and olive oils production, consumption, and exportation. Extra virgin olive oils are particularly important for the national agroindustrial sector, for the aspects related to the production territory (authenticity), and for the link with the Mediterranean Diet. However, at the same time, because of economical purposes, it is also one of the products most subjected to adulteration. The determination of the multi-elemental profile of extra-virgin olive oils has aroused increasing interest in the scientific community due to its possible application in geographical traceability studies. The determination of the multi-elemental profile in extra-virgin olive oil is, however, one of the most difficult analytical challenges, due to the high viscosity of the matrix, high organic load increasing the matrix effect and the possibility of interferences. Furthermore, the extremely low concentration of elements makes it extremely susceptible to contamination during pre-treatment of the sample. Analysis of existing literature has revealed that microwave digestion (with HNO3 and sometimes with the addition of H2O2) and ultrasound-assisted extraction are the sample pre-treatment procedures most widely used. However, some authors highlighted that the elemental content variability in different samples, even with the same geographical origin, can also be influenced by the different pre-treatment techniques. To overcome these difficulties, a method for the analysis of the multielemental profile of extra virgin olive oils was developed using HR ICP-AES PlasmaQuant 9100 equipped with an organic kit sample introduction system. This new method allows to directly analyse the extra virgin olive oil without the need for mineralization or extraction. Extra virgin olive oils, in fact, are only diluted in solvents with low viscosity before direct aspiration. This "dilute and shoot" approach offers the advantage of less sample preparation and handling, significantly reducing the risk of sample handling errors.

The quality of coffee is affected by the amount of oxygen present in the packaging. A maximum oxygen content is authorized to avoid oxidation of coffee during the shelf life, which would lead to off-taste in coffee cup. Oxygen content in the packaging can be measured by Fluorescent Decay, as described in ASTM F2714-08 (2021). However, this is only possible for transparent packaging. If it is not the case, direct sampling in the packaging is necessary. This requires a minimum amount of headspace in the pack. This minimum amount is defined by the oxygen sensor technology. In the case of limited headspace, gas chromatography is one of the promising options because of the limited amount of gas sample required but also because of the high accuracy and good precision of the tool. Development of any alternative packaging goes along with oxygen barrier measurement. At the production level, oxygen barrier properties might also need to be monitored for quality purposes. In this contribution, we propose to discuss a novel method for the determination of oxygen content in new coffee packaging by considering the challenges of new materials and measurements in production environment (at-line tool) i.e robustness of the material, time of the analysis and cost, repeatability of the measurement... Our contribution proposes a new way of sampling from the packaging when direct sampling gives unsatisfying results especially when low amount of oxygen needs to be measured in classical ambient environment. Together with a micro-GC, a sampling station connected to vacuum and a home-made hermetic chamber to isolate the sample from the environment. The sampling process is in two steps. Gas sampling being destructive, special care has been given to improve trueness and robustness of the measurement. Moreover, the proposed solution is a plug and play on actual set-up and does not require modification of existing set-ups. Finally, the measurement uncertainty has been evaluated based on the different components of the measurement chain. The results demonstrated that the proposed method was reliable and accurate with a detection limit of 0.1% oxygen. Furthermore, the method was found to be highly reproducible and showed excellent stability over time.