DETERMINATION OF CONTAMINANTS IN FISHERY PRODUCTS TO SUPPORT FOOD SAFETY

The contamination of fish and fishery products poses significant challenges to food safety, necessitating a comprehensive understanding of pollutants and their potential risks. This thesis focuses on different contaminants such as Persistent Organic Pollutants (POPs) as defined by the Stockholm Convention [1] and Persistent bioaccumulative toxic substances (PBTs), Potentially Toxic Elements (PTEs), whose study remains crucial for consumer protection; Perfluoroalkyl Substances (PFASs) some of which are POPs and Microplastics (MPs); these two classes have been particularly considered due to their condition of contaminants of emerging interest. The study employs advanced analytical techniques, such as Liquid Chromatography coupled to High-Resolution Mass Spectrometry (LC-HRMS), Gas Chromatography tandem Mass Spectrometry (GC-MS/MS), Inductively coupled plasma-optical emission spectrometry (ICP-OES) and Fourier-transform infrared spectroscopy (µFT-IR), to investigate the presence and concentrations of PFASs, and other POPs, PTEs, and MPs respectively in various fish species and products. In addition to the analytical aspect, the thesis explores the potential health implications associated with the consumption of contaminated fishery products, considering both acute and chronic effects. Special attention is given to vulnerable populations, such as pregnant women and children as well as high consumers, who may be more susceptible to the adverse effects of these contaminants, considering the unique characteristics of each contaminant class. As emerging environmental contaminants, PFASs have drawn increased attention due to their prevalence in aquatic ecosystems and potential health implications. So, the first article focuses on PFASs, tracing their occurrence in seabass (Dicentrarchus labrax), seabream (Sparus aurata), perch (Perca fluviatilis), Mediterranean shad (Alosa agone), and European whitefish (Coregonus lavaretus). Through LC-HRMS analysis, the study reveals the presence of PFBA and PFOS in both lake and sea fish, with PFBS exclusively found in lake fish. The observed concentrations were used to estimate the intake of PFOS, highlighting that the recommended tolerable weekly intake (TWI) by EFSA was not exceeded, even for the 99th percentile consumers. This underscores the significance of assessing the impact of aquatic pollution on food safety. The research contributes to build a database on PFASs in fish, evaluating contamination levels, and aiding in the formulation of reliable risk assessments for the consumer population. Addressing the presence of POPs in fishery products, the research utilizes GC-MS/MS analysis to assess their concentrations and compliance to regulatory limits. So, in the second article, the investigation turns to POPs in European seabass, gilthead seabream, and Mediterranean shad from Northern Italy lakes. GC-MS/MS analysis demonstrates that none of the analytes exceeded established maximum limits, and substances without specific limits remained below provisional tolerable daily intake (PTDI) levels. This study highlights the importance of monitoring and regulatory measures in maintaining the safety of fishery products and minimizing risks associated with pollutant exposure. The third article analyses PFAS and PTE in anchovies (Engraulis encrasicolus), a staple of the Italian diet. In the face of a paucity of previous data on these contaminants in anchovies, the study uncovers low levels of PFAS and PTE, stating that the assessed risk is reassuring for consumers, even those with higher consumption habits. This research highlights the need for continued vigilance in monitoring emerging contaminants and their potential impact on food safety. The inclusion of Microplastics (MPs) in the study acknowledges the emerging concern of plastic pollution in aquatic environments. The research characterizes the presence of MPs in fish different tissues, namely gills, gastrointestinal tract, and fillet, focusing on potential human exposure through fish consumption. So, the final article addresses the pervasive issue of microplastics in seabream and seabass from Mediterranean aquaculture facilities. The study identifies the gastrointestinal tract as a primary site of plastic accumulation, with higher contamination observed in fish from specific geographical areas, such as Turkey. The research sheds light on the potential human exposure through fish consumption, confirming the presence of MPs also in the edible tissues, and prompts reflection on sustainable aquaculture practices to mitigate pollution and safeguard food safety. Overall, this thesis emphasizes the importance of a multidimensional approach to the study of contaminants in fish and fishery products, and the articles collectively contribute to a nuanced understanding of the complex interplay between pollution in the aquatic environment and its profound implications for food safety, emphasizing the importance of continued research, monitoring, and regulatory efforts to ensure the integrity of fishery products in Italy. The utilization of different matrices, such as fresh fish and canned products, coupled with advanced analytical methods, provides a more comprehensive understanding of the distribution, bioaccumulation, and potential risks associated with PFASs and other POPs, PTEs, and MPs. The outcomes contribute to the enhancement of food safety protocols and regulatory measures in the seafood industry.