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A recent European Regulation further restricted the use of bisphenol A in food-contact materials, reducing its limit of migration. However, all analytical systems of control are aimed at identifying and quantifying the molecules of this monomer without taking in consideration the possible presence of its oligomers, species originating from material degradation and able to follow an in-vivo hydrolysis providing bisphenol A generation. Thus, the presence of oligomers of polycarbonate deriving by unreacted species or polymer degradation can be considered a hidden source of several bisphenol A units, that remains outside the control of legislation and should be considered of high concern. This work was focused on the identification and the description of kinetics of release of different molecules migrating from polycarbonate food contact materials to simulants and to a model food sample such as melted chocolate. Analyses were performed by UHPLC system coupled to a Q-Exactive mass spectrometer. Targeted and untargeted analysis through data dependent acquisition mode allowed to detect the occurrence of several species deriving from polycarbonate, and permitted to investigate the polymer degradation pattern and explore the correlation of the recorded amounts of each product with age, hours of usage, and washing cycles of the plastic items.

The interest towards "substances of emerging concerns" referred to objects intended to come into contact with food is recently growing. Such substances can be found in traces in simulants and in food products put in contact with plastic materials. In this context, it is important to set up analytical systems characterized by high sensitivity and to improve detection parameters to enhance signals. This work was aimed at optimizing a method based on UHPLC coupled to high resolution mass spectrometry to quantify the most common plastic additives, and able to detect the presence of polymers degradation products and coloring agents migrating from plastic re-usable containers. The optimization of mass spectrometric parameter settings for quantitative analysis of additives has been achieved by a chemometric approach, using a full factorial and d-optimal experimental designs, allowing to evaluate possible interactions between the investigated parameters. Results showed that the optimized method was characterized by improved features in terms of sensitivity respect to existing methods and was successfully applied to the analysis of a complex model food system such as chocolate put in contact with 14 polycarbonate tableware samples. A new procedure for sample pre-treatment was carried out and validated, showing high reliability. Results reported, for the first time, the presence of several molecules migrating to chocolate, in particular belonging to plastic additives, such Cyasorb UV5411, Tinuvin 234, Uvitex OB, and oligomers, whose amount was found to be correlated to age and degree of damage of the containers.

Non-intentionally added substances (NIAS) released from polycarbonate tableware were evaluated through untargeted analysis by UHPLC-ESI-Orbitrap. Migration experiments from fifteen samples of different age were performed using ethanol 95% and isooctane as food simulants. High-resolution mass spectrometry permitted the identification of oligomers derived from polycarbonate degradation and traces of colouring agents. Data were analysed with the aim of exploring a possible correlation between type and amount of different oligomers and age of the samples. It has been found out for the first time that the pattern of polycarbonate degradation products observed in new samples was different from that of old samples. Colouring agents were found to be released in higher amount from new samples than from old ones. The work shows the high potential of the technique employed and its importance in the field of control related to safety concern.

Materials that come in contact with foods are potential sources of chemical food contamination. Consequently, characterization of their composition is of paramount importance considering the possible occurrence of several unknown molecules such as non-intentionally added substance (NIAS), residual monomers, degradation products, plastic additives and organic colorants. Previous studies concerning the characterization in terms of composition are focalized in the recognition of additives. To the best author's knowledge there are no scientific data about the composition of a plastic material in terms of colorants. In this work, an analytical method employing capillary ultra high-performance liquid chromatography and electrospray ionization quadrupole orbitrap high-resolution mass spectrometry (UHPLC-ESI Q-orbitrap) was exploited for characterization of polycarbonate for food contact material. Data-dependent experiments for targeted and untargeted analysis were employed after a total dissolution of polycarbonate samples and extraction of its components. The presence of common additives such as antioxidants and UV absorbers was confirmed by targeted analysis, while, the untargeted approach combined with the high mass accuracy of orbitrap technology allowed to identify for the first time some polycarbonate degradation products and the organic dyes effectively used for the coloration of plastic objects intended to come in contact with food. The present study shows the high potential of this technique in the field of material characterization aimed at food safety evaluation.

A new UHPLC-ESI-Orbitrap method for the identification and the quantitative determination of bisphenol A and some common additives employed in plastic manufacturing has been developed and validated. The method has been applied to evaluate the migration from 14 samples of tableware of different age and degree of surface damage, in both ethanol and isooctane (used as food simulants according to EU plastic regulation). Bisphenol A, three UV light absorbers, and one whitening agent were detected and quantified. Data were analyzed with the aim of exploring a possible correlation between bisphenol A and additives release, ageing, and surface integrity. A high correlation between age of samples, surface damage, and bisphenol A migration has been evaluated, while the release of additives was not correlated with other parameters. Obtained data showed for the first time that the release of bisphenol A seems to be more connected to ageing than to scratches and cracks occurrence. Graphical Abstract Bisphenol A and additives released by polycarbonate tableware: influence of ageing and surface damage.