Les matériaux au contact des aliments (MCDA) constituent un enjeu majeur pour les industriels européens de l’alimentation et de l’emballage d’autant que les MCDA doivent être produits selon les bonnes pratiques de fabrication et être en accord avec les règlementations, notamment le règlement cadre européen 1935/2004. Les MCDA constituent une source potentielle de contamination des aliments car ils peuvent transférer des constituants aux aliments par migration. Parmi les MCDA, les matériaux papiers-cartons sont les plus utilisés après les matériaux plastiques et leur taux de recyclage en Europe était de 72% en 2015 et il ne cesse d’augmenter. En plus des substances dites intentionnelles (SI), des substances non intentionnelles (SNI) peuvent migrer du MCDA vers l’aliment ; elles peuvent être des impuretés, des produits de dégradation, des contaminants provenant des matériaux recyclés etc. Actuellement, de nombreuses SNI ne sont pas identifiées. La présence potentielle de SNI et la nature complexe de ces matériaux rendent difficile l’étude des MCDA papiers-cartons recyclés. Ce projet de thèse a pour objectif d’évaluer le danger lié de ces matériaux. Pour cela, des papiers-cartons recyclés ont été prélevés le long d’une chaine de production (du papier-carton à recycler de début de chaine au papier-carton issu du processus de recyclage), extraits dans l’eau puis lyophilisés. Des analyses chimiques ont été réalisées par spectrophotométrie et par des méthodes chromatographiques (HPLC, GC-MS, LC-MS, ICP-MS). Ces analyses ont montré la présence d’un plus grand nombre de substances dans le papier-carton de début de chaine par rapport au papier-carton de fin de chaine de recyclage. Parmi les composants détectés, des substances naturelles ont été identifiées dans les deux extraits étudiés, provenant notamment du bois qui est la matière première utilisée pour la fabrication du papier (polymères de cellulose, d’hémicellulose et de lignine, acides gras, sucres, acides résiniques ou encore des phénols). D’autres substances identifiées comme additifs ou contaminants ont été caractérisées dans les extraits étudiés, dont bisphénols, des molécules appartenant à la famille des phthalates, des amines aromatiques ou encore des hydrocarbures saturés d’huiles minérales. Il est à souligner qu’une grande partie des substances identifiées dans le produit de début de chaine étaient absentes du produit de fin de chaine. En parallèle des analyses chimiques, des biotests ont été réalisés afin d’identifier des mécanismes d’action et des potentiels effets « cocktail ». Grâce à une batterie de biotests, les effets des extraits sur des cibles toxicologiques ont été étudiés sur différentes lignées cellulaires humaines (deux lignées hépatiques HEpG2 et HepaRG, la lignée hERα-HeLa-9903 et la lignée MDA-kb2): cytotoxicité, génotoxicité et potentiel perturbateur endocrinien. A la plus forte concentration testée, seul l’extrait de produit de fin de chaine a entrainé un effet cytotoxique sur la lignée MDA-kb2. Cependant, les mêmes conditions de test ont montré que les produits de départ et de fin de chaine pouvaient entrainer un stress oxydant dans les lignées hépatiques utilisées. L’évaluation de la génotoxicité a montré des effets génotoxiques des deux papiers-cartons étudiés. Cependant, contrairement aux lésions du matériel génétique induites par le produit de départ, les dommages de l’ADN dus au produit de de fin de chaine pourraient ne pas être réparables pas les systèmes de réparation cellulaires et entrainer des mutations chromosomiques. Enfin, l’étude du potentiel perturbateur endocrinien a mis en évidence des activités oestrogéniques et antiandrogéniques dose-dépendantes des extraits étudiés. Ainsi, la mise en corrélation des résultats d’analyses chimiques et toxicologiques permet d’offrir une stratégie pertinente pour l’évaluation du danger lié aux MCDA, afin d’aider les industriels dans l’évaluation du risque des potentiels NIAS présents dans ces matériaux. / Food contact materials (FCM) are a major issue of concern for European packaging and food companies as FCM must be produced in accordance with the good manufacturing practices and be in compliance with European Regulation 1935/2004/UE. FCM could be a potential source of food contamination because they could release chemicals by a phenomenon called migration. Among FCM, paperboards are the most common materials after plastics and the recycling rate of paperboards is high and was 72% in Europe in 2015. In addition to started substances also called Intentionally Added Substances (IAS), Non-Intentionally Added Substances (NIAS) such as impurities, degradation products, contaminants from recycled materials etc, are also able to migrate from the FCM to food and many of them are not always fully characterized. Assessing the risk of recycled paperboards FCM is difficult because of NIAS and as recycled paperboards can be complex mixtures of substances. This thesis project uses a methodology combining chemical analysis and in vitro bioassays to evaluate the potential hazard of recycled food contact paperboard extracts. For this study, recycled paperboards have been sampled at different steps a food packaging production chain (the starting paperboard of the beginning of the production chain and the end paperboard issued from the recycling process), extracted with water and the dry matter content was recovered by freeze-drying. Chemical analysis of the extracts was performed by spectrophotometry and by chromatographic methods (HPLC, GC-MS, LC-MS and ICP-MS). Chemical analysis showed the presence of a higher number of substances in the starting paperboard than the end paperboard issued from the recycling process. Among these substances, several natural substances were detected in both extracts such as wood extractives (polymers of cellulose, hemicellulose and lignin, fatty acids, sugars, resin acids and phenols). Other substances identified as additives and contaminants were characterized in both extracts such as bisphenols, phthalates, aromatic amins or mineral oil saturated hydrocarbons. It is important to precise that a large number of the substances of the starting paperboard were not detected in the end paperboard. In parallel to chemical characterization, bioassays were used as relevant tools to identify mechanisms of action and potential “cocktail effects”. A battery of bioassays has been performed using different human cell lines (two hepatic cell lines HepG2 and HepaRG, the hERα-HeLa-9903 cell line and the MDA-kb2 cell line) to check toxicological endpoints which are relevant to low exposure: cytotoxicity, genotoxicity and potential endocrine disruption. No cytototoxic effects of both extracts were observed on both human hepatic cell lines HepG2 and HepaRG neither on the HeLa 9903 cell line; whereas the end paperboard extract had cytotoxic effects on MDA-kb2 cells at the highest tested concentration. However, in the same conditions, the starting and the recycled end paperboard extracts were able to induce oxidative stress in the used cell lines. The results of the genotoxicity study showed genotoxic effects of the starting paperboard and the end paperboards. The DNA damage induced by the starting paperboard in the used cellular models might be repaired by cell repair systems. In contrast, data of this study suggest that the end paperboard was able to induce DNA damage that might turn into chromosomal mutations. Data of the endocrine disruption potential showed that the tested FCM paperboard extracts induced significant agonist and dose dependent estrogenic and antiandrogenic activities in the used cell lines. The correlation of the results of the in vitro toxicological study and chemical analysis offers a relevant strategy for hazard assessment of FCM in order to help manufacturers to manage the risk of NIAS.

Doctorat en Sciences / info:eu-repo/semantics/nonPublished

Food contact materials are materials that are intended to come into contact with food, and we are exposed to different types of chemicals that exist in the packages on a daily basis. In this study, a battery of effect‑based in vitro cellular bioassays was used to evaluate the presence of bioactive compounds in commonly used food contact materials made of paper and cardboard, retrieved from the Swedish market. Sample extracts were tested at concentrations 0.3, 1, 3 and 10 mg food contact material/mL cell culture medium. The use of effect-based bioassays allowed for screening of multiple health-relevant endpoints in a non-targeted approach. Hence, taking unknown substances and mixtures into consideration when addressing potential toxicity of the materials. In essence, detection of bioactivity could be considered as moderate to high in assays of positive effects. Antiandrogenic and antiestrogenic effects were found in 72% of the samples, followed by 47% bioactivity in the Nrf2 assay. No androgenic effect was detected. Usage of effect-based bioassays allows for high sensitivity and low detection limits, and these can be used as a first approach to evaluate package materials to ensure the safety of consumers. / Livsmedelsförpackningar är material som är avsedda att komma i kontakt med livsmedel. Vi exponeras för olika typer av kemikalier som existerar i dessa förpackningar varje dag. I denna studie användes ett batteri av effektbaserade in vitro bioanalytiska metoder för att undersöka förekomst av bioaktiva ämnen i vanligen använda livsmedelsförpackningar tillverkade av papper och kartong, insamlade från den svenska marknaden. Provextrakten testades i koncentrationerna 0.3, 1, 3 och 10 mg livsmedelsförpackning/mL cellmedium. Att använda effektbaserade bioanalyser möjliggör undersökning av flertalet hälsorelevanta effekter genom en icke-riktad strategi. På så sätt tas okända substanser och komplexa blandningar i beaktande. Andelen bioaktiva prover kan anses måttlig till hög för positiva analyser. Antiandrogena och antiöstrogena effekter detekterades i 72% av proverna, följt av 47% bioaktivitet i Nrf2 analysen. Ingen agonistisk androgen effekt observerades. Att använda effektbaserade bioanalyser möjliggör hög sensitivitet och detektion vid låga koncentrationer, därför kan dessa användas som ett första steg för att evaluera förpackningsmaterial för att säkra konsumenternas hälsa.

(AJ) Food contact materials pose a risk to human health due to a variety of contaminants which they can release into food. These compounds, migrants, include aromatic hydrocarbons, dialkyl phthalates, bisphenols, printing ink photoinitiators, and perfluoroalkyl compounds. The determination of all these substances can be expensive and time-consuming since universally applicable analytical approaches are not available nowadays. This work attempted to develop methods for the simultaneous determination of migrants from all of the mentioned groups in paper-based food contact materials and fatty food. A total of 68 contaminants were studied in paper products using liquid chromatography and gas chromatography coupled with tandem mass spectrometry detection. All analytes were isolated simultaneously using the modified "QuEChERS" method. This method demonstrated acceptable recovery and repeatability for most analytes in the validation study; LOQs ranged from 1.3 to 220 µg/kg. Analysis of 132 real paper products confirmed the occurrence of almost all studied analytes, which were often present in complex mixtures and at concentrations up to 628 mg/kg. A total of 41 potential contaminants were monitored in fatty foods by liquid chromatography with tandem mass detection. Contamination of the mobile phase by...

(AJ) Food contact materials pose a risk to human health due to a variety of contaminants which they can release into food. These compounds, migrants, include aromatic hydrocarbons, dialkyl phthalates, bisphenols, printing ink photoinitiators, and perfluoroalkyl compounds. The determination of all these substances can be expensive and time-consuming since universally applicable analytical approaches are not available nowadays. This work attempted to develop methods for the simultaneous determination of migrants from all of the mentioned groups in paper-based food contact materials and fatty food. A total of 68 contaminants were studied in paper products using liquid chromatography and gas chromatography coupled with tandem mass spectrometry detection. All analytes were isolated simultaneously using the modified "QuEChERS" method. This method demonstrated acceptable recovery and repeatability for most analytes in the validation study; LOQs ranged from 1.3 to 220 µg/kg. Analysis of 132 real paper products confirmed the occurrence of almost all studied analytes, which were often present in complex mixtures and at concentrations up to 628 mg/kg. A total of 41 potential contaminants were monitored in fatty foods by liquid chromatography with tandem mass detection. Contamination of the mobile phase by...