Tommaso Pacini

Mycotoxins, including sterigmatocystin (STC), aflatoxicol (AFL), aflatoxin B₁ (AFB₁), and its metabolite aflatoxin M₁ (AFM₁), represent a major food safety concern in the dairy industry due to their high toxicity and thermal stability. While AFM₁ in milk is strictly regulated, there is a substantial lack of specific guidelines and scientific data regarding its behavior and enrichment factors (EFs) in buffalo-derived products. Furthermore, knowledge gaps persist regarding the transfer and stability of co-occurring molecules like STC and AFL. This study evaluated the distribution and fate of AFM₁, STC, and AFL during traditional, laboratory-scale cheesemaking of buffalo mozzarella and ricotta. Fourteen trials were conducted using bulk tank milk naturally contaminated with AFM₁, alongside an exploratory trial utilizing toxin-free milk artificially spiked with all three targets. Mass balance and specific EFs were calculated across all processing streams. AFM₁ was detected in all raw milk samples, showing a strong affinity for caseins. Approximately half of the initial milk AFM₁ content was retained in mozzarella (50.3 ± 3.3%), whereas ricotta retained only a minor fraction (6.9 ± 0.7%), with the majority lost in the second whey (30.7 ± 1.3%). The mean EFs were 2.3 ± 0.3 for mozzarella and 1.1 ± 0.2 for ricotta. AFL was never detected in milk samples while STC was mainly present at concentrations < 1 ng/kg. In the spiked trial, AFL demonstrated stability with an EF of 1.5 in mozzarella, while STC displayed potential degradation within the milk matrix and during sample storage. The experimental EFs determined for buffalo mozzarella and ricotta are lower than the standard factors currently applied by Italian regulations for non-bovine dairy products. These accurate, matrix-specific estimations are essential to prevent the under-reporting of non-compliant samples and to refine international consumer risk assessment models.

Despite the widespread use of dithiocarbamate fungicides such as maneb, mancozeb, metiram, propineb, thiram, and ziram detected, according to EU legislation, via common degradation product carbon disulfide (CS₂), recent and comprehensive reviews on analytical methods for their determination in plant-based foods are lacking. Given the well-documented toxicity shown by the experimental model for these pesticides, including neurotoxicity and endocrine disruption, harmonized and reliable analytical protocols are crucial for food safety monitoring and regulatory compliance. Dithiocarbamates, beyond CS₂ release, have been associated with immunotoxicity, thyroid dysfunction, and potential carcinogenicity, raising further concern regarding chronic dietary exposure. Their metabolites may disrupt enzymatic activity and oxidative balance, enhancing systemic toxicity. Early methods, had limited sensitivity, poor reproducibility, and relied on hazardous solvents, reducing practical value. Although later advancements improved detection limits, modern procedures, including those proposed by the European Union Reference Laboratory (EURL), still show limitations. The EURL-recommended protocol involves acid hydrolysis using concentrated HCl, extraction with isooctane, heating to 85 °C, and rapid ice-bath cooling, which poses environmental concerns. Recovery efficiency remains inconsistent in some cases, and reproducibility within commodity groups is poor. This review discusses the status of methods for determining dithiocarbamates as individual compounds and via CS₂ moiety.

The widespread use of agrochemicals raises concerns about environmental impacts, particularly on pollinators, such as bees, which serve as bioindicators of contamination. Developing methods to assess contamination risks in bioindicators supports regulatory frameworks, including EU regulations on the maximum residue limits (MRLs) for pesticides in food and the environment. This study presents the development and validation of two complementary analytical methods (LC–MS/MS and IC–HRMS) for highly polar pesticide (HPP) detection and quantification in bee matrices. Both methods were validated according to document SANTE/11312/2021 v2. LC–MS/MS was validated with a limit of quantification (LOQ) of 0.005 mg/kg for all the analytes. Repeatability at 0.005, 0.010, 0.020, and 0.100 mg/kg showed RSD_r from 1.6% to 19.7% and recoveries between 70% and 119%. Interlaboratory precision at 0.020 mg/kg across two labs showed RSD_R from 5.5% to 13.6%, with recoveries between 91% and 103%. The IC–HRMS method achieved LOQs of 0.01 mg/kg (glufosinate, N-acetyl glufosinate, MPPA, glyphosate, N-acetyl glyphosate, N-acetyl AMPA) and 0.1 mg/kg (fosetyl, phosphonic acid, AMPA), with mean recoveries in repeatability conditions from 84% to 114% and RSD_r from 2% to 14%. Intralaboratory precision showed mean recoveries from 87% to 119%, with RSD_wR values between 10% and 18%. These methods enable accurate monitoring of HPP contamination, supporting risk assessment and sustainable agriculture.

Alternaria toxins (ATs) are a group of toxins produced by Alternaria fungi that frequently contaminate tomatoes and tomato products. Recently, the European Food Safety Authority evaluated ATs for their genotoxic and carcinogenic properties. Alternaria infestation is often controlled using ad hoc treatment strategies (fungicides). In this study, two analytical methods were developed, validated and applied for the determination of five ATs and 195 pesticides in tomato products collected from the Italian market. Two distinct groups, organic (n = 20) and conventional (n = 20) Italian tomato sauces, were characterized in depth. Tenuazonic acid, alternariol and alternariol monomethyl ether were found up to 517, 27 and 7.1 µg/kg, respectively, while pesticides were detected between 0.0026 and 0.0421 mg/kg in conventional products, and, interestingly, up to 0.0130 mg/kg in organic products. No correlation emerged between the detected levels of ATs and pesticides and the type of tomato cultivation, but the probability of pesticide contamination in conventional products was eight times higher than in organics. Some considerations about exposure assessment and risk characterization for ATs were also proposed in the overall population and in more sensitive and/or exposed subgroups, underlining the need for new focused toxicological and monitoring studies to establish reliable reference values. Moreover, these data highlight that fungicide treatments may not protect tomatoes from ATs contamination, although it may remove fungi infestation. As organic product consumption is increasing, it is important to lay down dedicated regulations for maximum permitted levels to ensure the food safety of these products that are often perceived by consumers as a healthier and environmentally friendlier choice.

The detection and quantification of polar pesticides in liquid chromatography coupled with mass spectrometry present significant analytical challenges. This study compares the performance of three LC columns (Hypercarb™, Raptor Polar X™, and Anionic Polar Pesticide™) in separating and quantifying eleven polar pesticides in chicken eggs using a score-based methodology. Analytes include glyphosate, its metabolites, and other high-polarity pesticides like Ethephon, Glufosinate, and Fosetyl aluminum, included in the EU’s official control plan. Polar pesticides, characterized by high polarity and hydrophilicity, lead to analytical issues such as poor retention and unconventional peak shapes with traditional reversed-phase methods. Their weak interaction with hydrophobic stationary phases complicates separation, necessitating specific stationary phases to enhance retention and selectivity. This study evaluates these columns’ efficacy in complex matrices like chicken eggs and other food samples. Chromatographic separation was performed using a UPLC system coupled with a Q-TOF mass spectrometer; extraction and purification involved freeze-out, centrifugation, and filtration steps. The study highlights the critical role of column selection in achieving accurate and reliable separation and quantification of highly polar analytes in matrices of animal origin, offering in the meantime an easy-to-apply methodology of selection for the right determination of the best chromatographic column for different purposes.

Mycotoxin contamination of feed and feed materials represent a serious health hazard. This study details the occurrence of aflatoxin B₁ (AFB₁), zearalenone (ZEN) and ochratoxin A (OTA) in 826 feed and 617 feed material samples, collected in two Italian Regions (Umbria and Marche) from 2018 to 2022 analyzed using a UPLC-FLD platform. The developed method was validated and accredited (ISO/IEC 17025) with satisfactory accuracy and precision data obtained in repeatability and intralaboratory reproducibility conditions. Feed had a higher incidence of contaminated samples (26%) with respect to feed materials (6%). AFB₁ was found up to 0.1045 mg/kg in cattle feeds and 0.1234 mg/kg in maize; ZEN was detected up to 6.420 mg/kg in sheep feed while OTA was rarely reported and in lower concentrations (up to 0.085 mg/kg). Co-contamination of at least two mycotoxins was reported in 0.8% of the analyzed samples. The incidence of above maximum content/guidance level samples was 2% for feed and feed materials while almost 3-fold-higher for maize (5.8%) suggesting how mycotoxin contamination can affect some matrices more than others. Obtained data can be useful to improve official monitoring plans and therefore further raise awareness of this issue between agriculture stakeholders, healthcare entities and non-professionals.