Contaminants  |  Recherche scientifique Contaminants in the food chain - 10 October 2024 Food safety research conference in Luxembourg

Dr. Chantra Eskes, Feed and Contaminants (FEEDCO) Unit, European Food Safety Authority (EFSA)

Feed and food chemical contaminants are substances that are unintentionally present in food or feed as a result of e.g. environmental contamination, process contamination, as natural toxins or as unauthorised veterinary medicines. Chemical contaminants may be harmful to humans and animals.

EFSA provides scientific advice and carries out risk assessments on a wide range of chemical contaminants that can be present in food and feed. This work is carried out by EFSA’s Panel on Contaminants in the Food Chain. The Authority also collects occurrence data on contaminants in food and feed and supports the coordination of data collection and monitoring by Member States.

EFSA’s scientific advice helps policy makers take informed decisions on managing risks of food and feed contaminants. This includes e.g., establishing maximum levels, monitoring and/or recommending strategies to reduce exposure to contaminants present in food and feed.

The presentation will discuss the latest scientific opinions on food contaminants, and provide an overview of the ongoing activities regarding food and feed contaminants. 

David Schuh*, Nadine Daleiden, Danielle Ruckert and Claude Schummer

Administration des Services Techniques de l‘Agriculture – Division des laboratoires, service d’analyse des engrais, des aliments pour animaux et d’alcools. 72, avenue Lucien Salentiny, L-9080 Ettelbruck

* Presenting author

Antibiotics are frequently used in agriculture to cure animals in case of disease, and a multitude of different antibiotics and anticoccidials are available today. The proper use of these products has been regulated in the EU regulation 1831/2003 on additives for use in animal nutrition. This regulation also forbids some products that were used in the past but have been banned because of toxic and/or carcinogenic properties for humans or animals.

Improper use of antibiotics in factories or on the farm may lead to cross-contaminations and residues of antibiotics may be found in feed not supposed to contain any antibiotics. These residues may end up in products like milk, eggs or meat. This can lead to problems in food production, in particular for fermented products like cheese or sausages. Furthermore, a constant background level of small amounts of antibiotics may cause resistances to antibiotics in bacteria.

The aim of this study was the development of a multiresidue method based on solid-liquid extraction and UHPLC-MS/MS detection. The method has been validated on 19 antibiotics from 10 different classes and has been applied to 15 cereal based feed samples. No antibiotics above the LOQ have been detected, only traces of Doxycyclin and Amprolium (below 100 µg/kg) have been measured in two samples. This confirms the suitability of the method for the detection of antibiotics in feed. Further studies will aim to increase the amount of monitored compounds and to include food matrices relevant to human health. 

Stefania-Delia Isaic, Environmental Health Group, Luxembourg Institute of Science and Technology (LU)

Traditionally, food safety heavily relies on epidemiological data, which is often not available for new products, or on animal studies, which poses ethical issues regarding animal welfare and can only partly predict the human effects. Today’s scientific efforts are focused on developing New Approach Methodologies (NAMs), proposing microphysiological systems (MPS) as complex in vitro models that can closely mimic the in vivo situation. If coupled with multi-OMICs approaches that provide a complete overview of biological processes triggered by chemical exposure, MPS can help reconstruct the molecular mechanism of action (MOA) and inform on key biomarkers.

The main goal of the TULI project (OC/EFSA/IDATA/2023/02) is to establish and demonstrate an NAMs-derived -OMICs analytical bioinformatic standardised workflow for safety assessment of food and feed related chemicals, which will allow to derive reliable human reference points and health-based guidance values (HBGVs). The workflow will rely on multi-OMICs approach, comprising transcriptomics, metabolomics and epigenomics analysis. Using a well-established dual-organ MPS (PhysioMimix®, CN-Bio), we will recreate two axes (intestine-liver and lung-liver) by connecting advanced in vitro systems. In the first phase of the project, exposure to 6 data-rich substances will generate a training dataset that will support the refinement of the bioinformatics pipeline initially built based on a literature review and data gap analysis. We will capture two dimensions of exposure, by identifying acute and long-term biomarkers. In the second phase, exposure to 25 data-poor chemicals and downstream analysis of targeted OMICs will further validate the predictive power of the pipeline.

Sofie Schrijvers¹, Mia Eeckhout¹, Liesbeth Jacxsens¹, Bram Miserez²*

¹ Ghent University, Dept. Food Technology, Food Safety and Health, Ghent, Belgium

² Ciboris npo, Zwijnaarde, Belgium

* Presenting author

Lupins are gaining importance as a food source, both for human animal consumption, because of their high protein content. However, they are an allergen and contain quinolizidine alkaloids, toxic secondary metabolites. We have studied the presence of quinolizidine alkaloids on the Belgian food market, both in lupin based products and in animal products from animals fed with lupins, as well as the fate of the alkaloids during food processing.

An analytical method for various food matrices was developed for seven quinolizidine alkaloids and applied to over 300 food samples, selected based on market research. A food frequency questionnaire was used to determine the consumption and as a basis for a risk assessment. Total quinolizidine alkaloid consumption was estimated to be 3.9 ± 27.3 µg/kg body weight per day, with those consuming dry lupins, lupin flower or canned lupins to be at the highest risk of consumption of quinolizidine alkaloids.

Twenty samples calve feed was analyzed as well, together with the resulting veal and liver from 10 animals fed with this feed. A total quinolizidine alkaloid content of 42 ± 28 mg/kg feed was measured. In the resulting animal products, mainly lupanine was detected at about 3 orders of magnitude less.

Several food processes were imitated on a laboratory scale and the amount of quinolizidine alkaloids were tracked through the different processing steps. Most a stabile at high temperatures and only soaking the beans removes the alkaloids from the food products.

Dr. Véronique Sirot

Risk Assessment Department, French agency for food, environmental and occupational health & safety (ANSES)

In France, food contamination is monitored in a regulatory framework through monitoring and surveillance programs managed by the competent ministries. In the 2000s, this knowledge was supplemented and strengthened by national Total Diet Studies (TDSs). TDSs are recognized worldwide as one of the most cost-effective surveys to assess food contamination, dietary chronic exposure of the population to a large set of chemical substances, and associated health risks.

To date, three TDSs have been conducted in France: TDS1 (2001-2005) and TDS2 (2006-2011) on the general population and a study targeting non-breastfed infants and children under three years of age (infant TDS, 2010-2016). Another study (TDS3) was initiated in 2019 to update the exposure data and the risk assessment of French adults and children over three years of age for more than 300 substances.

The results of the three first French TDSs showed that, for more than 90% of the substances, long-term dietary exposure was deemed as tolerable for the population considered. For the remaining substances, identified as concerns or for which the risk could not be ruled out, measures to reduce the exposure of the population were proposed. Management and/or research recommendations were also formulated in order to refine the conclusions relating to the risk associated with exposure to certain compounds in future studies.

Besides providing a huge database for researchers, the French TDS results represent a major tool for the French public authorities, as well as industry and other stakeholders, as an aide to decision-making in risk management (control and regulation) at the national, European and international levels.

Dr. Luc Schuler, Luxembourg Veterinary and Food Administration (LU)

Per- and polyfluoroalkyl substances (PFAS) and PFAS-like fluorinated pesticides have attracted attention because of their persistence, bioaccumulation potential and possible adverse effects on living organisms. Due to the extreme persistence of these substances, nicknamed "eternal chemicals", impacts on the environment and human health are likely to increase. Thees pollutants are linked to adverse health effects including increased risk of certain cancers, diabetes and for having potential endocrine disruption properties amongst others. Diet is an important source of PFAS and PFAS-like fluorinated pesticides exposure. The main objectives of this study were to carry out market surveys and investigate the occurrence of PFASs in commonly consumed food items in order to evaluate the exposure to these substances and consequently contributing to regulate these contaminants in specific categories. Moreover, monitoring these substances enables long-term risk-based management of PFAS exposure in humans, livestock, and game.

Charlotte B. A. Stoffels¹*, Tina B. Angerer¹, Gilles Frache¹, Hervé Robert2, Sébastien Cambier¹, Maria A. Subirana³, Dirk Schaumlöffel³, Tom Wirtz¹, Arno C. Gutleb¹, Muriel Mercier-Bonin2, Jean-Nicolas Audinot¹

¹ Luxembourg Institute of Science and Technology, Belvaux, Luxembourg

² Toxalim, Université de Toulouse, INRAE, INP-ENVT, INP-EI-Purpan, Université de Toulouse 3 Paul Sabatier, Toulouse, France.

³ CNRS, Université de Pau et des Pays de l'Adour, E2S UPPA, Institut des Sciences Analytiques et de Physico-Chimie pour l’Environnement et les Matériaux (IPREM), UMR 5254, Pau, France.

* Presenting author

Perfluoroalkylated substances (PFAS), like perfluorooctanoic acid (PFOA), have been widely used in industry and consumer products, making them prevalent in the environment. These chemicals are persistent, accumulating in human bodies, and pose significant health risks. Although the digestive system is the first impacted upon oral exposure, their effects on the gastrointestinal tract and gut-liver axis remain largely unknown. The FLUO-GUT project aimed to investigate PFOA uptake and effects on human intestines and liver using in vivo (mice) and in vitro (human cell line) models, combined with advanced mass spectrometry (MS) techniques.

Mice and human cell models exposed to PFOA were analyzed using complementary MS methods. LC-MS/MS detected and quantified PFOA and other biomolecules, while various MS imaging (MSI) techniques studied PFOA localization from tissue to sub-cellular levels. Molecular information at the tissue level was obtained using TOF-SIMS and MALDI-MSI, while elemental information at the (sub-)cellular level was gathered with high-resolution SIMS techniques, including FIB-SIMS and NanoSIMS.

The mass spectrometry workflow showed that PFOA accumulates in both the intestines and liver, with higher levels in the liver in mice. PFOA localized in specific tissue areas, particularly in goblet cells in the intestines and hepatocyte cytosol in the liver. In the human Caco-2 cell model, PFOA was also mainly found in the cytosol. This study provided crucial data on intracellular PFOA concentrations, filling a gap in PFAS research. These findings highlight the value of MS analysis in understanding PFOA's impact on the gastrointestinal tract and liver, opening new avenues for toxicology research.

List of abbreviations

MS: Mass spectrometry; MSI: Mass spectrometry imaging; LC-MS/MS: Liquid chromatography with tandem MS; SIMS: Secondary ion mass spectrometry; TOF-SIMS: Time-of-flight SIMS; MALDI-MSI: Matrix-assisted laser deposition ionization MSI; FIB-SIMS: Focus ion beam platform combined with SIMS; NanoSIMS: Nanoscale SIMS

Vincent Berthé, Cédric Guignard*, Julie Soulier, Daniel Schmidt

Luxembourg Institute of Science and Technology (LIST), 5 avenue des Hauts-Fourneaux L-4362 Esch-sur-Alzette

* Presenting author

Polyethylene terephthalate (PET) is extensively used for beverage bottles, due to its advantageous properties, such as low gas permeability, good mechanical strength, transparency, reflectivity, ease of processing, and affordability. As the third largest packaging polymer, PET recycling, especially of PET bottles, has significantly advanced thanks to cleaning technologies. Advantageously, mechanical recycling of PET is environmentally favourable compared to producing new resin.

EU regulations outline the procedures for recycling companies to gain approval for producing food-grade mechanically recycled PET (rPET), focusing on the safety of migrating substances. Beverage companies using PET with recycled content must also comply with European food contact material (FCM) legislation. Additionally, non-intentionally added substances (NIAS) must meet safety requirements following the European regulation.

Benzene can be found as a contaminant of rPET. It originates from heat-induced decomposition of rPET impurities such as polyvinylchloride (PVC), a secondary material coming from the sorting step of the mechanical recycling. Contamination of rPET by benzene could represent a public health concern, as it may migrate into the contents of the rPET package during conditioning and storage.

This work describes the analytical protocols developed to measure the benzene contamination sources of rPET materials and explores the effect of a new process that attempts to address such issues in the context of rPET use in packaging applications. Our results demonstrate the possibility to reduce benzene levels while maintaining an acceptable level of rPET performance. These improvements are promising in the context of material quality, food safety and environmental impact for the use of rPET in packaging applications.

Emma Arnesdotter¹*, Charlotte Stoffels¹, Arno C. Gutleb¹, Tommaso Serchi¹.

¹Department of Environmental Health and Innovation, Luxembourg Institute of Science and Technology, Luxembourg.

* Presenting author

Per- and polyfluoroalkyl substances (PFAS) are a broad chemical class of complex and persistent compounds used in several industrial and consumer applications, including firefighting foam, food packaging, non-stick repellents, and waterproof products. When PFAS chemicals leach into water sources from industrial and waste sites they can contaminate drinking water supplies. Additionally, plants, fish, and animals absorb PFAS from the environment. This results in human exposure through the intestinal system by consuming contaminated drinking water and food products. Intestinal absorption of most PFAS is considerable in mammals, including humans (EFSA 2020). Yet, sufficient toxicity information for risk assessment is available for only a few PFAS compounds.

The SCENARIOS project incorporates an extensive list of experimental tasks to collect experimental toxicity information on PFAS and human health. These tasks include in vitro experiments in advanced 3D models of barrier tissues related to the three major routes of exposure, i.e. ingestion, inhalation, and dermal contact.

In the SCENARIOS project, an intestinal in vitro co-culture system will be employed to evaluate the exposure to selected subgroups of data-poor PFAS. Transcriptomic dose-dependent dynamics coupled with functional assays and measurements of PFAS barrier crossing/uptake are used to inform on the putative mode of action and possible long-term effects of PFAS as contaminants in the food chain. The toxicity data generated with these advanced models will ultimately be integrated with PFAS cheminformatics to support the development of a chemocentric, multilayer read-across framework for grouping PFAS in risk assessment processes.

References:

EFSA 2020 - EFSA CONTAM Panel (EFSA Panel on Contaminants in the Food Chain), 2020. Scientific Opinion on the risk to human health related to the presence of perfluoroalkyl substances in food. EFSA Journal 2020;18(9):6223, 391 pp. https://doi.org/10.2903/j.efsa.2020.6223

Gea Guerriero*, Margaux Thiry, Sylvain Legay, Kjell Sergeant, Samuel Jourdan, Diego Rios-Salgado, Jean-Francois Hausman, Jenny Renaut

Luxembourg Institute of Science and Technology, 5, Rue Bommel, L-4940 Hautcharage, Luxembourg

* Presenting author

Dedifferentiated plant cells, which are cells that have re-entered the division cycle and over-proliferate under the stimulus of exogenously supplied phytohormones, represent a promising avenue in food and feed applications. Unlike traditional plant cultivation methods, dedifferentiated plant cells can be mass-cultured in controlled, closed and sterile environments, the bioreactors, thereby reducing land and water use, minimizing the need for chemical inputs, lowering carbon emissions, and preventing soil degradation. Such a technology is compliant with Good Manufacturing Practices (GMP), scalable, season-independent, as well as free from contaminants and pathogens, hence conforming to the One Health principle. There is growing awareness of the economic potential of plant cell suspension cultures and a trend towards cellular agriculture, the production of typical agricultural products from cells rather than through traditional farming of plants and animals, is becoming clear. Plants are rich sources of bioactive phytochemicals, e.g., antioxidants useful for applications such as in nutraceuticals and cosmetics. The Luxembourg Institute of Science and Technology (LIST) is currently investigating the cultivation of plant cell suspensions in laboratory- up to pilot-scale bioreactors to produce added-value bioactives. Two examples will be presented: Cannabis sativa and Centaurea cyanus cell suspension cultures. The results obtained by LIST will be shown and discussed in the light of their potential future use for food- and feed-related applications.

Hiba Mohammed Taha

Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg

Since its inception in 2015, NORMAN Suspect List Exchange (NORMAN-SLE) has become a vital knowledge base, facilitating the identification and monitoring of contaminants across air, soil, and water. The NORMAN-SLE offers an open and FAIR platform for the exchange of suspect screening lists enriched with accompanying expert knowledge and references. With over 118 suspect lists from more than 70 contributors, the database encompasses over 120,000 unique substances, including pharmaceuticals, pesticides, per- and polyfluoroalkyl substances (PFAS), as well as chemicals associated with food contact materials (FCMs).

NORMAN-SLE plays a crucial role in data collection, providing lists that aid in identifying chemicals likely to migrate into food, posing potential risks to human health. The integration of NORMAN-SLE data into major chemical databases like PubChem and the US EPA’s CompTox Chemicals Dashboard enhances accessibility and utility, offering researchers and regulators additional functionality for chemical analysis and risk assessment.

In the context of food safety, NORMAN-SLE supports risk management by offering relevant suspect lists such as the S26 MYCOTOXINS, S54 European Food Safety Authority Priority Substances, S77 Food Contact Chemicals Database (FCCDB),  S112 Migrating & Extractable Food Contact Chemicals (FCCmigex) by Food Packaging Forum and the PFAS subsets : S117 PFASFCCDB S118 and PFASFCCMIGEX. These lists enable targeted screening for contaminants, facilitating early detection and regulatory action to mitigate risks associated with chemical migration into the food chain. Through its collaborative and integrative approach, NORMAN-SLE significantly contributes to the global efforts in safeguarding food safety and public health.