Histamine contamination was evaluated on 474 batches (3130 determinations) of fish products collected in Puglia and Basilicata (southern part of Italy) during the years 2015–2019, using a high-throughput two-tier approach involving a screening (ELISA test) and confirmatory method (HPLC/FLD with o-phthalaldehyde derivatization). Histamine concentration >2.5 mg kg⁻¹ was detected in 51% of total batches with the 2.5% of non-compliance. Except for two samples of fresh anchovies, all non-compliant samples were frozen, defrosted and canned tuna. Among 111 fresh tuna batches, 9 had a content of histamine between 393 and 5542 mg kg⁻¹, and scombroid poisoning cases were observed after their consumption. Good quality canned tuna and ripened anchovies sold in Italy was observed. Furthermore, the analysis of the processing technology and storage practice critical points were reported in this study, with useful considerations to minimize the histamine risk for consumers. Finally, based on these results, several considerations about risk exposure were reported.

Under the name of lipophilic marine toxins, there are included more than 1000 toxic secondary metabolites, produced by phytoplankton, with the common chemical property of lipophilicity. Due to toxicological effects and geographical distribution, in European legislation relevant compounds are regulated, and their determination is accomplished with the reference liquid chromatography-tandem mass spectrometry method. In this study a modified ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method has been developed for the identification and quantification of EU-regulated lipophilic toxins. The method optimization included a refinement of SPE-C18 clean-up, in order to reduce matrix interferences. Improved LC conditions and upgraded chromatographic ammonia-based gradient ensured the best separation of all analytes and, in particular, of the two structural isomers (OA and DTX2). Also, different MS parameters were tested, and confirmation criteria finally established. The validation studies confirmed that all parameters were satisfactory. The requirements for precision (RSD% < 11.8% for each compound), trueness (recoveries from 73 to 101%) and sensitivity (limits of quantification in the range 3–8 µg kg⁻¹) were fulfilled. The matrix effect, ranging from −9 to 19%, allowed the use of a calibration curve in solvent (3–320 µg kg⁻¹ in matrix) for quantification of real samples. Method relative uncertainty ranged from 12 to 20.3%. Additionally, a total of 1000 shellfish samples was analysed, providing a first preliminary surveillance study that may contribute to the knowledge of lipophilic marine toxins contamination. Increase in algae proliferation events and intoxication cases, EFSA suggestions for modification of maximum permitted levels and toxicity equivalency factors, and new studies of important toxic effects underline that implementation of reference methods still represents an important task for health and food safety laboratories.

The aim of this study was to estimate the aflatoxin M₁ (AFM₁) contamination in raw milk and processed milk (pasteurized or UHT) collected from two regions in Italy (Puglia and Basilicata) during a 12-year period: 2012–2023. A total of 1017 milk samples were analyzed first proceeding with screening analysis by enzyme-linked immunosorbent assay (ELISA), and suspected non-compliant samples (AFM₁ concentration higher than 0.042 µg/kg) were then analyzed by high performance liquid chromatographic with fluorimetric detection (HPLC/FLD) confirmation method. AFM₁ concentration ≥ 0.005 µg/kg (ELISA limit of quantitation) was detected in 553 of the 1017 milk samples (54.4%). AFM₁ levels exceeding the European Union maximum limit (ML) of 0.050 µg/kg were detected in 70 samples, 49 of which were determined as non-compliant samples (4.8%). Particularly high concentrations of AFM₁, exceeding 200 µg/kg, were found in four samples, three raw milk and one pasteurized. Regarding this risk exposure study, only the MOE values obtained under “high exposure scenario” were lower than 10,000, while those calculated from the overall mean values resulted as not of concern.

The illegal treatment of tuna with nitrite is a significant food safety concern. The risk may be due to not only the high nitrite levels and the possible formation of N-Nitrosamines but also to the possible increase in biogenic amines and microbial load and also pathogens. This study optimized the treatment of red tuna (Thunnus thynnus) with nitrite solutions and then determined several chemical (histamine, total volatile basic nitrogen (TVBN), biogenic amines, nitrite/nitrate, ascorbic acid, and sulfites) and microbiological (total microbial count, Enterobacteriaceae, Vibrionaceae, coagulase-positive staphylococci, Salmonella, Escherichia coli) parameters, comparing the results obtained with fresh samples with those obtained with treated samples after 5 days of storage (4 °C). The effect of such treatment on samples voluntarily contaminated with some pathogens was also investigated. The results indicate that if the products are characterized by suitable hygienic quality, the total microbial load and the levels of histamine and TVBN after 5 days of storage are below the legal limits, and no health risk subsists. The growth of pathogens/histaminogens (Salmonella and Morganella morganii) was also substantially inhibited during storage. Thus, this work confirmed that the high nitrite amounts and the possible development of N-nitrosamines represent the only significant food safety concerns.