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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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

A sensitive and selective analytical method for the simultaneous separation and quantitative determination of aflatoxins B1, B2, G1 and G2 in foodstuffs and materials for feed has been validated. The method is based on high performance liquid chromatography with on-line post-column photochemical derivatization and fluorescence detection. The chromatographic separation of aflatoxins was accomplished using a C18 column eluted with an isocratic mobile phase consisting of water, methanol and acetonitrile. The sample preparation required a simple extraction of aflatoxins with MeOH/H2O (80:20, v/v) and a purification step by immunoaffinity column cleanup. The total analysis time, including sample preparation and chromatographic separation, did not exceed 40 min with a run time of 10 min. The on-line photochemical derivatization ensures better results in terms of simplicity, sensitivity and reproducibility with respect to chemical derivatization techniques, and provides an increase of the peak resolution and an extent of automation in comparison with the electrochemical ones. The procedure for the determination of aflatoxins in food samples and cereals for animal consumption was extensively validated following Regulation (EC) No. 882/2004. Detection limits in wheat bran samples of 0.08 µg kg-1 for AFB1, 0.02 µg kg-1 for AFB2, 0.16 µg kg-1 for AFG1 and 0.04 µg kg-1 for AFG2 were attained. The method allows high recovery with mean values ranging from 72 to 94% and it satisfies the necessary requirements for sensitivity, linearity, selectivity, precision and ruggedness, demonstrating the conformity of the method with provisions of Regulation (EC) No. 401/2006. [ABSTRACT FROM AUTHOR]

Poisoning of domestic animals is frequently caused by anticoagulant rodenticides. Validation and applications of a rapid and reliable method for the simultaneous determination of 8 anticoagulant rodenticides (bromadiolone, brodifacoum, coumachlor, coumafuryl, coumatetralyl, difenacoum, flocoumafen, and warfarin) in baits and animal livers using high-performance liquid chromatography with fluorescence detection are reported herein. The methodology was validated by an in-house validation model at 2.5 mg/kg, which is the level commonly found in the tissues of poisoned domestic animals. The 8 anticoagulants can be determined at the concentration range of 1.25-100 mg/kg with determination coefficients higher than 0.992. A recovery value from 70% to 109% was observed for all the studied molecules. The results of the validation process demonstrate suitability for application in official analysis and for monitoring purposes of animal poisoning by anticoagulant rodenticides.

The occurrence of the fumonisins B(1) and B(2) in maize-based food products marketed in Italy was examined. A simply and reliable chromatographic method with fluorimetric detection and postcolumn o-phtalaldehyde derivatization was used for a monitoring of 100 samples (8 flours, 21 corn-meal, 16 snacks, 7 maize samples, 13 gluten-free products, and 35 corn-flakes) bought in local supermarkets during the years 2008 and 2009. The presence of both fumonisins B(1) and B(2), at a concentration higher than 15 μg/kg, was observed in all samples of corn-meal and maize-flour, in 75% of snacks, in 57% of maize samples, in 54% of gluten-free products, and in 29% of corn-flakes. A total of 7 samples including 4 corn-meals, 2 maize-flours, and 1 maize showed a value exceeding the maximum level fixed in the Regulation 1126/2007/EC; no positive sample was observed in corn-flakes, snacks, and gluten-free foods. Fumonisins contamination, on the whole range of maize-based food products analyzed, emphasizes the need of improve agricultural practices, and increase official control and monitoring studies.

A high performance liquid chromatographic method with fluorimetric detection for the determination of aflatoxin M1 (AFM1) in milk has been optimized and validated according to Commission Decision 2002/657/EC by using the conventional validation approach. The procedure for determining selectivity, recovery, precision, decision limit (CC(alpha)), detection capability (CC(beta)) and ruggedness of the method has been reported. The results of the validation process demonstrate the agreement of the method with the provisions of Commission Regulation 401/2006/EC. The mean recovery calculated at three levels of fortification (0.5, 1.0, and 1.5-fold the MRL) was 91% and the maximum relative standard deviation value for the within-laboratory reproducibility was 15%. Limit of detection (LOD) and limit of quantitation (LOQ) values were 0.006 microg kg(-1) and 0.015 microg kg(-1) while the CC(alpha) and CC(beta) values were 0.058 microg kg(-1) and 0.065 microg kg(-1), respectively. The relative expanded measurement uncertainty of the method was 7%. The method was not affected by slight variations of some critical factors (ruggedness minor changes) as pre-treatment and clean-up of milk samples, thermal treatment and different storage conditions, as well as by major changes valued in terms of milk produced by different species (buffalo, goat and sheep). The method allowed accurate confirmation analyses of milk samples, resulted positive by the screening method. In fact, the Z-score values attained in a proficiency test round were well below the reference value of 1, proving the excellent laboratory performances.