Friends or Foes? Emerging Impacts of Biological Toxins.

Toxins are substances produced from biological sources (e.g., animal, plants, microorganisms) that have deleterious effects on a living organism. Despite the obvious health concerns of being exposed to toxins, they are having substantial positive impacts in a number of industrial sectors. Several toxin-derived products are approved for clinical, veterinary, or agrochemical uses. This review sets out the case for toxins as 'friends' that are providing the basis of novel medicines, insecticides, and even nucleic acid sequencing technologies. We also discuss emerging toxins ('foes') that are becoming increasingly prevalent in a range of contexts through climate change and the globalisation of food supply chains and that ultimately pose a risk to health.

Rapid Assessment of Fish Freshness for Multiple Supply-Chain Nodes Using Multi-Mode Spectroscopy and Fusion-Based Artificial Intelligence.

This study is directed towards developing a fast, non-destructive, and easy-to-use handheld multimode spectroscopic system for fish quality assessment. We apply data fusion of visible near infra-red (VIS-NIR) and short wave infra-red (SWIR) reflectance and fluorescence (FL) spectroscopy data features to classify fish from fresh to spoiled condition. Farmed Atlantic and wild coho and chinook salmon and sablefish fillets were measured. Three hundred measurement points on each of four fillets were taken every two days over 14 days for a total of 8400 measurements for each spectral mode. Multiple machine learning techniques including principal component analysis, self-organized maps, linear and quadratic discriminant analyses, k-nearest neighbors, random forest, support vector machine, and linear regression, as well as ensemble and majority voting methods, were used to explore spectroscopy data measured on fillets and to train classification models to predict freshness. Our results show that multi-mode spectroscopy achieves 95% accuracy, improving the accuracies of the FL, VIS-NIR and SWIR single-mode spectroscopies by 26, 10 and 9%, respectively. We conclude that multi-mode spectroscopy and data fusion analysis has the potential to accurately assess freshness and predict shelf life for fish fillets and recommend this study be expanded to a larger number of species in the future.

Food allergen analysis: A review of current gaps and the potential to fill them by matrix-assisted laser desorption/ionization.

Food allergy remains a public health, business, and regulatory challenge. Risk analysis (RA) and risk management (RM) of food allergens are of great importance and analysis for food allergens is necessary for both. The current workhorse techniques for allergen analysis (enzyme linked immunosorbent assay [ELISA] and real-time polymerase chain reaction) exhibit recognized challenges including variable and antibody specific responses and detection of species DNA rather than allergen protein, respectively. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) enables protein identification, with potential for multiplex analysis and traceability to the System of International units (SI), aiding global measurement standardization. In this review, recent literature has been systematically reviewed to assess progress in LC-MS/MS and define the potential and benefits of matrix-assisted laser desorption/ionization-time-of-flight MS (MALDI-ToF-MS) technology for allergen analysis. MALDI-ToF-MS of initially intact protein is already applied to verify in silico-derived peptide sequences for LC-MS/MS analysis. We describe the origins of MALDI and its future perspectives, including affinity bead-assisted assays coupled to MALDI. Based on the proliferation of reliable and reproducible MALDI-based clinical applications, the technique should emulate the detection capability (sensitivity) of established allergen detection techniques, whilst reducing technical support and having equivalent multiplexing potential to competing techniques, for example, LC-MS/MS and ELISA. Although unlikely to offer inherent SI traceability, MALDI-based allergen analysis will complement existing MS approaches for allergens. Affinity bead-MALDI appears capable of higher throughput at lower cost per sample than almost any existing technique, enabling repeated sub-sampling as a way to reduce representative sampling issues.

The potential and applicability of infrared spectroscopic methods for the rapid screening and routine analysis of mycotoxins in food crops.

Infrared (IR) spectroscopy is increasingly being used to analyze food crops for quality and safety purposes in a rapid, nondestructive, and eco-friendly manner. The lack of sensitivity and the overlapping absorption characteristics of major sample matrix components, however, often prevent the direct determination of food contaminants at trace levels. By measuring fungal-induced matrix changes with near IR and mid IR spectroscopy as well as hyperspectral imaging, the indirect determination of mycotoxins in food crops has been realized. Recent studies underline that such IR spectroscopic platforms have great potential for the rapid analysis of mycotoxins along the food and feed supply chain. However, there are no published reports on the validation of IR methods according to official regulations, and those publications that demonstrate their applicability in a routine analytical set-up are scarce. Therefore, the purpose of this review is to discuss the current state-of-the-art and the potential of IR spectroscopic methods for the rapid determination of mycotoxins in food crops. The study critically reflects on the applicability and limitations of IR spectroscopy in routine analysis and provides guidance to non-spectroscopists from the food and feed sector considering implementation of IR spectroscopy for rapid mycotoxin screening. Finally, an outlook on trends, possible fields of applications, and different ways of implementation in the food and feed safety area are discussed.

Immuno-Enriched Microspheres - Magnetic Blade Spray-Tandem Mass Spectrometry for Domoic Acid in Mussels.

Paramagnetic microspheres can be used in planar array fluorescence immunoassays for single or multiplex screening of food contaminants. However, no confirmation of the molecular identity is obtained. Coated blade spray (CBS) is a direct ionization mass spectrometry (MS) technique, and when combined with triple quadrupole MS/MS, it allows for rapid confirmation of food contaminants. The lack of chromatography in CBS, though, compromises the specificity of the measurement for unequivocal identification of contaminants, based on the European Union (EU) regulation. Therefore, a rapid and easy-to-use immuno-magnetic blade spray (iMBS) method was developed in which immuno-enriched paramagnetic microspheres replace the coating of CBS. The iMBS-MS/MS method was fully optimized, validated in-house following the EU 2021/808 regulation, and benchmarked against a commercial lateral flow immunoassay (LFIA) for on-site screening of DA. The applicability of iMBS-MS/MS was further demonstrated by analyzing incurred mussel samples. The combination of immunorecognition and MS/MS detection in iMBS-MS/MS enhances the measurement's selectivity, which is demonstrated by the rapid differentiation between the marine toxin domoic acid (DA) and its structural analog kainic acid (KA), which cannot be achieved with the LFIA alone. Interestingly, this first-ever reported iMBS-MS/MS method is generic and can be adapted to include any other immuno-captured food contaminant, provided that monoclonal antibodies are available, thus offering a complementary confirmatory analysis approach to multiplex immunoassay screening methods. Moreover, thanks to its speed of analysis, iMBS-MS/MS can bridge the logistics gap between future large-scale on-site testings using LFIAs and classical time-consuming confirmatory MS analysis performed in official control laboratories.

Tropane alkaloid contamination of agricultural commodities and food products in relation to consumer health: Learnings from the 2019 Uganda food aid outbreak.

Tropane alkaloids (TAs) are secondary plant metabolites derived mainly from Solanaceae plant families, with the most virulent invasive species being Datura stramonium. Datura stramonium commonly grows in cereal fields and produce TAs (e.g., hyoscyamine and scopolamine) which may accidentally contaminate cereals (and cereal-based foods) at occasionally high levels. Dietary exposure to TAs can be toxic and depending on the dose ingested can cause outcomes ranging from anticholinergic effects to acute poisoning and death. In 2019, 315 adults became ill and another five adults died in Uganda following consumption of a "Super Cereal" (a fortified blended food) that was later confirmed to be contaminated by TAs-a scenario which provoked this holistic review on TAs in foodstuffs. Thus, this article provides information on the history, development, occurrences, exposures, and human legislative and health benchmarks for TAs. It describes control strategies for reducing TA contamination of agricultural commodities and resultant health implications following consumption of TA contaminated foodstuffs. Adequate application of food safety control measures (including maximum limits) and good practices, from the start of cereal cultivation through to the final stages of manufacturing of food products can aid in the reduction of seeing toxic plants including D. stramonium in cereal fields.

Decontamination of aflatoxin B1 in peanuts using various cooking methods.

Peanut and its processed products are recurrently contaminated with aflatoxins (AFs) which are of potential public health concern. Among the different types of AFs, Aflatoxin B1 (B1) is the most frequently detected in peanuts over the maximum level (ML), and thus has warranted considerable research interest in the domain of food safety. In this study, we investigated the decontamination of B1 in three naturally-incurred lots (4, 12, and 40 µg/kg) of peanuts by a range of cooking treatments, including frying, pressure cooking, and roasting. B1 concentrations were determined by ultra-high performance liquid chromatography- fluorescence detection. The method provided a limit of quantification of 0.25 µg/kg for B1, which was much lower than any of its national and international MLs. The recoveries of B1 in fresh and cooked peanuts (positive-control) were in the range of 90-100%. Overall, all the cooking methods demonstrated a significant reduction in B1 loads. The degree to which the processing methods reduced the B1 content followed the pattern: roasting with a combination of NaCl and citric acid > pressure-cooking with a combination of NaCl and citric acid > frying. As the cooking procedures did not involve any complicated steps or sophisticated equipment, these could be readily adopted for decontamination or reduction in the level of B1 for a safer consumption of peanuts at the household level without affecting the organoleptic properties.

A Randomized Combined Channel Approach for the Quantification of Color- and Intensity-Based Assays with Smartphones.

Quantification of colorimetric assays with smartphones is being increasingly reported. However, a complete characterization of the performance of existing color spaces and single-color channels for optimum color/intensity change quantification is absent. Moreover, it has not been ascertained if it is necessary to utilize existing color spaces to reach optimal assay quantification. In this study, a randomized channel approach was adapted utilizing all single channels from RGB, HSV, and CieLab color space and all nonrepeating random combinations of two and three channels of these color spaces. Assays based on color or intensity change using pH strips and gold or carbon black nanoparticle-containing paper strips were optimized using this approach. Several novel channel combinations showed great promise, in terms of prediction error and interphone variation reduction, outperforming RGB, HSV, and CieLab color spaces. These novel combinations were used in a custom-developed smartphone application that performed automated background subtraction and polynomial regression for the quantification of a lateral flow assay for the detection of goat milk adulteration with cow milk and for pH prediction in soil. For the lateral flow assay the channel combination BSA was found optimum (mean average error = 36% ± 6%; R2 = 0.97). For the soil pH assay the channel combination RLC was found optimum (mean average error = 1.31% ± 0.02%; R2 = 0.997). The study has shown that nonclassical channel combinations for colorimetric quantification of specific assays are very promising and should be considered for smartphone-based analysis.

Towards a dietary-exposome assessment of chemicals in food: An update on the chronic health risks for the European consumer.

An informed opinion to a hugely important question, whether the food on the Europeans' plate is safe to eat, is provided. Today, the Europeans face food-borne health risks from non-communicable diseases induced by excess body weight, outbreaks caused by pathogens, antimicrobial resistance and exposures to chemical contaminants. In this review, these risks are first put in an order of importance. Then, not only potentially injurious dietary chemicals are discussed but also beneficial factors of the food. This review can be regarded as an attempt towards a dietary-exposome evaluation of the chemicals, the average European adult consumers could chronically expose to during their life-times. Risk ranking reveals that currently the European adults are chronically exposed to a mixture of potentially genotoxic-carcinogenic contaminants, particularly food process contaminants, at the potential risk levels. Furthermore, several of the contaminants whose dietary exposures pose risks appear to be carcinogens operating with a genotoxic mode of action targeting the liver. This suggests that combined health risks from the exposure to a mixture of the chemical contaminants poses a greater potential risk than the risks assessed for single compounds. Over 100 European-level risk assessments are examined. Finally, the importance of a diversified and balanced diet is emphasized.

Worldwide contamination of food-crops with mycotoxins: Validity of the widely cited 'FAO estimate' of 25.

Prior to 1985 the Food and Agriculture Organization (FAO) estimated global food crop contamination with mycotoxins to be 25%. The origin of this statement is largely unknown. To assess the rationale for it, the relevant literature was reviewed and data of around 500,000 analyses from the European Food Safety Authority and large global survey for aflatoxins, fumonisins, deoxynivalenol, T-2 and HT-2 toxins, zearalenone and ochratoxin A in cereals and nuts were examined. Using different thresholds, i.e. limit of detection, the lower and upper regulatory limits of European Union (EU) legislation and Codex Alimentarius standards, the mycotoxin occurrence was estimated. Impact of different aspects on uncertainty of the occurrence estimates presented in literature and related to our results are critically discussed. Current mycotoxin occurrence above the EU and Codex limits appears to confirm the FAO 25% estimate, while this figure greatly underestimates the occurrence above the detectable levels (up to 60-80%). The high occurrence is likely explained by a combination of the improved sensitivity of analytical methods and impact of climate change. It is of immense importance that the detectable levels are not overlooked as through diets, humans are exposed to mycotoxin mixtures which can induce combined adverse health effects.

The benefits of carbon black, gold and magnetic nanomaterials for point-of-harvest electrochemical quantification of domoic acid.

Gold nanostars (GNST), gold nanospheres (GNP) and carbon black (CB) are chosen as alternative nanomaterials to modify carbon screen-printed electrodes (c-SPEs). The resulting three kinds of modified c-SPEs (GNP-SPE, CB-SPE and GNSP-SPE) were electrochemically and microscopically characterized and compared with standardized c-SPEs after pretreatment with phosphate buffer by pre-anodization (pre-SPE). The results show outstanding electrochemical performance of the carbon black-modified SPEs which show low transient current, low capacitance and good porosity. A competitive chronoamperometric immunoassay for the shellfish toxin domoic acid (DA) is described. The performances of the CB-SPE, GNP-SPE and pre-SPE were compared. Hapten-functionalized magnetic beads were used to avoid individual c-SPE functionalization with antibody while enhancing the signal by creating optimum surface proximity for electron transfer reactions. This comparison shows that the CB-SPE biosensor operated best at a potential near - 50 mV (vs. Ag/AgCl) and enables DA to be determined with a detection limit that is tenfold lower compared to pre-SPE (4 vs. 0.4 ng mL-1). These results show very good agreement with HPLC data when analysing contaminated scallops, and the LOD is 0.7 mg DA kg-1 of shellfish. Graphical abstractSchematic representation of the magnetic bead-based immunoassay for the quantification of domoic acid (DA) in shellfish with nanomaterial-modified screen-printed electrodes. CB, carbon black; GNP, gold nanospheres; GNST, gold nanostars; MB, magnetic beads; DA-mAb, anti-DA monoclonal mouse antibody; HRP-pAb, horseradish conjugated polyclonal goat anti-mouse antibody; DA-BSA, bovine serum albumin conjugated DA; HQ, hydroquinone; BQ, benzoquinone.

Global metabolite profiles of rice brown planthopper-resistant traits reveal potential secondary metabolites for both constitutive and inducible defenses.

INTRODUCTION: Brown planthopper (BPH) is a phloem feeding insect that causes annual disease outbreaks, called hopper burn in many countries throughout Asia, resulting in severe damage to rice production. Currently, mechanistic understanding of BPH resistance in rice plant is limited, which has caused slow progression on developing effective rice varieties as well as effective farming practices against BPH infestation. OBJECTIVE: To reveal rice metabolic responses during 8 days of BPH attack, this study examined polar metabolome extracts of BPH-susceptible (KD) and its BPH-resistant isogenic line (IL308) rice leaves. METHODS: Ultra high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QToF-MS) was combined with multi-block PCA to analyze potential metabolites in response to BPH attack. RESULTS: This multivariate statistical model revealed different metabolic response patterns between the BPH-susceptible and BPH-resistant varieties during BPH infestation. The metabolite responses of the resistant IL308 variety occurred on Day 1, which was significantly earlier than those of the susceptible KD variety which showed an induced response by Days 4 and 8. BPH infestation caused metabolic perturbations in purine, phenylpropanoid, flavonoid, and terpenoid pathways. While found in both susceptible and resistant rice varieties, schaftoside (1.8 fold), iso-schaftoside (1.7 fold), rhoifolin (3.4 fold) and apigenin 6-C-α-L-arabinoside-8-C-ß-L-arabinoside levels (1.6 fold) were significantly increased in the resistant variety by Day 1 post-infestation. 20-hydroxyecdysone acetate (2.5 fold) and dicaffeoylquinic acid (4.7 fold) levels were considerably higher in the resistant rice variety than those in the susceptible variety, both before and after infestation, suggesting that these secondary metabolites play important roles in inducible and constitutive defenses against the BPH infestation. CONCLUSIONS: These potential secondary metabolites will be useful as metabolite markers and/or bioactive compounds for effective and durable approaches to address the BPH problem.

Hydrophilic Divinylbenzene for Equilibrium Sorption of Emerging Organic Contaminants in Aquatic Matrices.

Hydrophilic divinylbenzene (DVB) (Bakerbond) has surfaced as a promising sorbent for active sampling of analytes from aqueous matrices over a very broad polarity range. Given this, hydrophilic DVB may likewise offer potential for passive sampling, if sorbent/water partitioning coefficients (Ksw) were to be available. In this work, static exposure batch experiments were performed to quantitatively study the equilibrium sorption of 131 environmentally relevant organic contaminants (P values ranging from -1.30 to 9.85) on hydrophilic DVB. The superior affinity of hydrophilic DVB, as compared to Oasis HLB, for compounds with a broad polarity range was confirmed by functional Fourier-transform infrared spectroscopy and Raman characterization, demonstrating the presence of carboxyl moieties. Concentration effects were studied by increasing compound concentrations in mixture experiments and resulted in the steroidal endocrine disrupting compounds in higher Ksw, while lower Ksw were obtained for the (alkyl)phenols, personal care products, pesticides, pharmaceuticals, and phthalates. Nevertheless, Ksw remained constant in the said design for equilibrium water concentrations at environmentally relevant seawater levels. An independent analysis of thermodynamic parameters (change in enthalpy, entropy, and Gibbs free energy) revealed the nature of the main partitioning processes. While polar (log P < 4) compounds were mainly served by physisorption, nonpolar (log P > 4) compounds also exhibited binding by multiple hydrogen bonding. In conclusion, this research facilitates the future application of hydrophilic DVB for active as well as passive sampling in the analysis of organic contaminants for monitoring purposes and for toxicity testing.

Electrochemical nanoprobe-based immunosensor for deoxynivalenol mycotoxin residues analysis in wheat samples.

Deoxynivalenol (DON) is a toxic secondary metabolite produced by several species of Fusarium fungi, which can be predominantly found in agricultural crops such as wheat. In livestock, deoxynivalenol-contaminated grain can produce vomiting, feed refusal, weight loss, and diarrhea. This paper reports an electrochemical immunosensor for the detection of residual DON mycotoxin in food samples. The device uses electrochemical nanoprobes (CdSNP-AbDON) and antigen biofunctionalized magnetic µ-particles (DON-BSAMP) to detect the mycotoxin. CdSNP-AbDON are prepared by labelling the DON-specific antibodies with CdS nanoparticles (CdSNPs). Nanoparticle size and CdSNP-AbDON conjugation ratio are characterized using TEM images. The metal ions released by the CdSNP are reduced at the working electrode and read by anodic stripping voltammetry. DON can be detected in PBST buffer with an IC50 of 6.74 ± 0.19 µg L-1. The high detectability of the immunosensor developed allows detection of DON residues in 50-fold diluted wheat extracts. The limit of detection (LOD, IC90) accomplished in wheat is of 342.4 µg kg-1, which is below the maximum residue limit (MRL, 1750 µg kg-1 for unprocessed durum wheat, 750 µg kg-1 for cereals intended for direct human consumption) established by the EU for this mycotoxin. The working range is in the interval between 610 and 6210 µg kg-1. The performance of the immunosensor was compared with the ELISA assay. DON naturally contaminated wheat samples were analyzed with the immunosensor, showing acceptable recoveries. Graphical abstract.

The Efficiency of Color Space Channels to Quantify Color and Color Intensity Change in Liquids, pH Strips, and Lateral Flow Assays with Smartphones.

Bottom-up, end-user based feed, and food analysis through smartphone quantification of lateral flow assays (LFA) has the potential to cause a paradigm shift in testing capabilities. However, most developed devices do not test the presence of and implications of inter-phone variation. Much discussion remains regarding optimum color space for smartphone colorimetric analyses and, an in-depth comparison of color space performance is missing. Moreover, a light-shielding box is often used to avoid variations caused by background illumination while the use of such a bulky add-on may be avoidable through image background correction. Here, quantification performance of individual channels of RGB, HSV, and LAB color space and ΔRGB was determined for color and color intensity variation using pH strips, filter paper with dropped nanoparticles, and colored solutions. LAB and HSV color space channels never outperformed the best RGB channels in any test. Background correction avoided measurement variation if no direct sunlight was used and functioned more efficiently outside a light-shielding box (prediction errors < 5%/35% for color/color intensity change). The system was validated using various phones for quantification of major allergens (i.e., gluten in buffer, bovine milk in goat milk and goat cheese), and, pH in soil extracts with commercial pH strips and LFA. Inter-phone variation was significant for LFA quantification but low using pH strips (prediction errors < 10% for all six phones compared). Thus, assays based on color change hold the strongest promise for end-user adapted smartphone diagnostics.

Development and in-house validation of a rapid and simple to use ELISA for the detection and measurement of the mycotoxin sterigmatocystin.

Sterigmatocystin (STG) is a highly toxic secondary fungal metabolite structurally closely related to the well-known carcinogenic aflatoxins. Its presence has been reported in grains and grain-based products as well as in other foodstuffs like nuts, green coffee beans, spices, beer and cheese. Due to the lack of suitable data on the occurrence of STG, in 2013, the European Food Safety Authority (EFSA) could not characterise its risk for human health and recommended that more data on STG in food and feed needed to be collected. In order to provide a new tool for the specific detection of STG, a competitive enzyme-linked immunosorbent assay (ELISA) was developed, optimised and validated in this study based on a sensitive monoclonal antibody specific to STG with no cross-reactivity with aflatoxins. The sample preparation method for rice, wheat and maize was based on a modified QuEChERS (quick, easy, cheap, effective, rugged and safe) approach. The assay was validated for the detection of STG in rice, wheat and maize in accordance with the guidelines for validation of semi-quantitative screening methods included in Commission Regulation (EU) 519/2014. The screening target concentration (STC) was set at 1.5 µg/kg. The cutoffs for rice, wheat and maize were 1.2, 1.2 and 1.3 µg/kg and the false suspected rates were 0.34, 1.15 and 0.78%, respectively. Good correlation was found between the results obtained by the STG ELISA and LC-MS/MS method for naturally contaminated rice samples. This validated method can be applied as a sensitive and high-throughput screening for the presence of STG in a range of agricultural commodities. Graphical abstract A new enzyme-linked immunosorbent assay based on an antibody specific to sterigmatocystin for the detection of this mycotoxin in corn, wheat and rice.

Advanced LC-MS-based methods to study the co-occurrence and metabolization of multiple mycotoxins in cereals and cereal-based food.

Liquid chromatography (LC) coupled with mass spectrometry (MS) is widely used for the determination of mycotoxins in cereals and cereal-based products. In addition to the regulated mycotoxins, for which official control is required, LC-MS is often used for the screening of a large range of mycotoxins and/or for the identification and characterization of novel metabolites. This review provides insight into the LC-MS methods used for the determination of co-occurring mycotoxins with special emphasis on multiple-analyte applications. The first part of the review is focused on targeted LC-MS approaches using cleanup methods such as solid-phase extraction and immunoaffinity chromatography, as well as on methods based on minimum cleanup (quick, easy, cheap, effective, rugged, and safe; QuEChERS) and dilute and shoot. The second part of the review deals with the untargeted determination of mycotoxins by LC coupled with high-resolution MS, which includes also metabolomics techniques to study the fate of mycotoxins in plants.

Food colors: Existing and emerging food safety concerns.

Food colors are added to different types of commodities to increase their visual attractiveness or to compensate for natural color variations. The use of these additives is strictly regulated in the European Union, the United States, and many other countries worldwide. There is a growing concern about the safety of some commonly used legal food colorants and there is a trend to replace the synthetic forms with natural products. Additionally, a number of dyes with known or suspected genotoxic or carcinogenic properties have been shown to be added illegally to foods. Robust monitoring programs based on reliable detection methods are required to assure the food is free from harmful colors. The aim of this review is to present an up to date status of the various concerns arising from use of color additives in food. The most important food safety concerns in the field of food colors are lack of uniform regulation concerning legal food colors worldwide, possible link of artificial colors to hyperactive behavior, replacement of synthetic colors with natural ones, and the presence of harmful illegal dyes-both known but also new, emerging ones in food. The legal status of food color additives in the EU, United States, and worldwide is summarized. The reported negative health effects of both legal and illegal colors are presented. The European Rapid Alert System for Food and Feed notifications and US import alerts concerning food colors are analyzed and trends in fraudulent use of color additives identified. The detection methods for synthetic colors are also reviewed.

Detection of freshwater cyanotoxins and measurement of masked microcystins in tilapia from Southeast Asian aquaculture farms.

Recently, there has been a rise in freshwater harmful algal blooms (HABs) globally, as well as increasing aquaculture practices. HABs can produce cyanotoxins, many of which are hepatotoxins. An ultra-performance liquid chromatography tandem mass spectrometry method was developed and validated for nine cyanotoxins across three classes including six microcystins, nodularin, cylindrospermopsin and anatoxin-a. The method was used to analyse free cyanotoxin(s) in muscle (n = 34), liver (n = 17) and egg (n = 9) tissue samples of 34 fish sourced from aquaculture farms in Southeast Asia. Conjugated microcystin was analysed by Lemieux oxidation to ascertain the total amount of microcystin present in muscle. Some tilapia accumulated free microcystin-LR in the muscle tissue at a mean of 15.45 µg/kg dry weight (dw), with total microcystin levels detected at a mean level of 110.1 µg/kg dw, indicating that the amount of conjugated or masked microcystin present in the fish muscle accounted for 85% of the total. Higher levels of cyanotoxin were detected in the livers, with approximately 60% of those tested being positive for microcystin-LR and microcystin-LF, along with cylindrospermopsin. Two fish from one of the aquaculture farms contained cylindrospermopsin in the eggs; the first time this has been reported. The estimated daily intake for free and total microcystins in fish muscle tissue was 2 and 14 times higher, respectively, than the tolerable daily intake value. This survey presents the requirement for further monitoring of cyanotoxins, including masked microcystins, in aquaculture farming in these regions and beyond, along with the implementation of guidelines to safeguard human health. Graphical abstract ᅟ.

Evaluation of tetrodotoxins in puffer fish caught along the Mediterranean coast of Spain. Toxin profile of Lagocephalus sceleratus.

Although consumption of Tetraodontidae species is prohibited in the EU, intoxications are still reported. The evaluation of tetrodotoxins (TTXs) by mass spectrometry (LC-MS/MS and LC-HRMS) and a screening immunoassay (mELISA) in tetraodontid fishes caught along the Western Mediterranean Sea revealed high concentrations of TTXs in Lagocephalus sceleratus while no TTXs were identified in L. lagocephalus and Sphoeroides pachygaster individuals. The high TTXs content found in the L. sceleratus analysed herein demonstrate the occurrence of highly toxic puffer fish in the Western Mediterranean Sea. Being L. sceleratus a recent invasive species in the Mediterranean, surveillance, risk assessment and risk management measures are necessary. The strategy used within this research work could be a valuable tool for future food safety monitoring.