DOCTORAL DISSERTATION Faculty of Chemistry Department of Trace Analysis Interaction problem between the environmentally friendly modern food contact materials (FCMs) and food Współczesne naczynia przyjazne środowisku – problem interakcji pomiędzy materiałem a żywnością 2025 M.Sc. Karolina Brończyk, Eng. Doctoral dissertation submitted to the Scientific Council of the Faculty of Chemistry, Adam Mickiewicz University in Poznań for the purpose of awarding the degree of Doctor of Chemical Sciences. Supervisors: Prof. UAM Agata Dąbrowska, PhD, DSc, Eng. Prof. Małgorzata Majcher, PhD, DSc, Eng. Faculty of Chemistry Adam Mickiewicz University in Poznań 2 Faculty of Chemistry Adam Mickiewicz University in Poznań 3 Acknowledgements I would like to express my gratitude to my Supervisor, Professor Agata Dąbrowska for support, commitment, kindness and invaluable substantive assistance throughout the years of my education at the School of Doctoral Studies. I would also like to express my sincere thanks to my Second Supervisor, Professor Małgorzata Majcher, for invaluable support, kindness and assistance during the research of volatile organic compounds at the Faculty of Food Science and Nutrition of the University of Life Sciences in Poznań. I sincerely thank Professor Anetta Hanć for valuable guidance and substantive support during the research tasks and writing of this dissertation. I would also like to thank Professor Adam Dąbrowski for allowing me to do a research internship, which contributed to the quality of scientific work. My sincere thanks also go to Dr. Adam Konieczka for his cooperation and support during the implementation of research projects. I would like to especially thank my Family and Friends for their patience, understanding, support and belief in me. I dedicate this work to my greatest Supporters – my Parents. Faculty of Chemistry Adam Mickiewicz University in Poznań 4 Faculty of Chemistry Adam Mickiewicz University in Poznań 5 Abstract The pursuit of sustainability in all aspects of public life is currently a fundamental global responsibility, due to the constantly deteriorating state of the environment. Numerous regulations have been introduced in the packaging sector (including the Plastics Directive). Based on these, new biodegradable and recyclable food contact materials (FCMs) have appeared on the consumer market, which may raise food safety concerns. The doctoral dissertation carried out a comprehensive characterization of the interactions between newly introduced FCMs and food. For this purpose, 13 FCMs (of plant origin, bio-based plastics) were selected and subjected to migration tests under different time and temperature conditions, using food or food simulants of different nature. A wide spectrum of chemical compounds (untargeted approach) and migration markers (targeted approach) were determined using analytical, sensory and statistical tools. This enabled the identification and quantification of various organic and inorganic contaminants that can easily migrate from FCMs to food and affect its sensory profile and quality. The obtained results clearly showed that some plant-based FCMs can distort the sensory profile of coffee and tea. Chemical compounds affecting noticeable undesirable changes include saturated and unsaturated carbonyl compounds (e.g., Strecker aldehydes: 3-methylbutanal and 2-methylbutanal), and saturated alcohols (e.g., hexan-1-ol, heptan-2-ol, octan-3-ol). In order to assess the influence of various factors (time and temperature of FCM-food contact, microwave radiation, type of food, chemical composition of food) on the intensity of FCM-food interactions, low-molecular-weight carbonyl compounds were selected as markers of undesirable changes. These compounds are ubiquitous in the environment, are reactive and undergo dynamic changes, and the optimized measurement procedure used allowed their monitoring at low concentration levels (ng/L). Consumer exposure to particularly hazardous compounds migrating (e.g., formaldehyde, bisphenol-A, toxic elements) from new FCMs to food was also estimated using specific migration limits (SML) or tolerable daily intake (TDI). The presented results and discussion provide a basis for deepening knowledge and understanding the nature of currently popular FCMs and their impact on the environment, and especially on food. Keywords: environmental pollution; food contact materials (FCMs); migration studies; food simulants; organic and inorganic contaminants; food safety; markers of changes; analytical tools; sensory analysis. Faculty of Chemistry Adam Mickiewicz University in Poznań 6 Streszczenie W obliczu nieustannie pogarszającego się stanu środowiska dążenie do zrównoważonego rozwoju w każdym aspekcie życia publicznego stanowi obecnie fundamentalny, globalny obowiązek. W sektorze opakowaniowym wprowadzono liczne regulacje prawne (m.in. Dyrektywę Plastikową), na mocy których na rynku konsumenckim zaczęły pojawiać się nowe, biodegradowalne i zdatne do recyklingu materiały do kontaktu z żywnością (ang. food contact materials; FCMs), co może budzić wątpliwości dotyczące bezpieczeństwa żywności. W rozprawie doktorskiej przeprowadzono kompleksową charakterystykę interakcji zachodzących między nowo wprowadzanymi FCMs a żywnością. W tym celu wybrano 13 FCMs (pochodzenia roślinnego i bioplastiki), które poddano badaniom migracji w różnych warunkach czasowych i temperaturowych, z wykorzystaniem żywności lub płynów modelowych imitujących żywność o różnym charakterze. W celu oceny bezpieczeństwa FCMs, oznaczono szerokie spektrum związków chemicznych (podejście nieukierunkowane) oraz markery migracji (podejście ukierunkowane) za pomocą narzędzi analitycznych, sensorycznych i statystycznych. Umożliwiło to zidentyfikowanie oraz skwantyfikowanie różnych zanieczyszczeń organicznych oraz nieorganicznych, które mogą łatwo migrować z FCMs do żywności i wpływać na jej profil sensoryczny i jakość. Uzyskane wyniki jednoznacznie wykazały, że niektóre FCMs pochodzenia roślinnego mogą zniekształcać profil sensoryczny kawy i herbaty, a do wiodących związków chemicznych wpływających na wyczuwalne, niepożądane zmiany można zaliczyć nasycone i nienasycone związki karbonylowe (m.in. aldehydy Streckera: 3-methylbutanal i 2-methylbutanal) i nasycone alkohole (np. heksan-1-ol, heptan- 2-ol, oktan-3-ol). W celu oceny wpływu różnych czynników (m.in. czasu i temperatury kontaktu FCM- żywność, promieniowania mikrofalowego, rodzaju żywności, składu chemicznego żywności) na intensywność interakcji FCMs-żywność, wybrano niskocząsteczkowe związki karbonylowe jako markery zachodzących, niepożądanych zmian. Związki te są wszechobecne w środowisku, są reaktywne i ulegają dynamicznym zmianom, a zastosowana zoptymalizowana procedura pomiarowa pozwoliła na ich monitorowanie na niskich poziomach stężeń (ng/L). Oszacowano również narażenie konsumentów na szczególnie niebezpieczne związki migrujące (np. formaldehyd, bisfenol-A, pierwiastki toksyczne) z nowych FCM do żywności przy użyciu limitów migracji specyficznej (SML) lub tolerowanego dziennego pobrania (TDI). Przedstawione wyniki i dyskusja stanowią podstawę do pogłębienia wiedzy i zrozumienia natury obecnie popularnych FCMs i ich wpływu na środowisko, a zwłaszcza na żywność. Słowa kluczowe: zanieczyszczenie środowiska; materiały do kontaktu z żywnością; badania migracji; płyny modelowe; organiczne i nieorganiczne zanieczyszczenia; bezpieczeństwo żywności; markery zmian; narzędzia analityczne; analizy sensoryczne. Faculty of Chemistry Adam Mickiewicz University in Poznań 7 List of symbols AD – anaerobic digestion ANT – anthracene BAM – bamboo bowl BET (isotherm) – Brunauer-Emmett-Teller (isotherm) BIOPP – bio-polypropylene cup BPA – bisphenol-A BPS – bisphenol-S CAGR – compound annual growth rate CE – circular economy CRMs - certified reference materials EDCs – endocrine disrupting compounds EFSA – European Food Safety Authority EMAS – eco-management and audit system EPP – expanded polypropylene bowl ETVS – environmental technology verification system EU – European Union FCMs – food contact materials FCS – food contact substances GCxGC-TOF/MS - comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry GC-ECD – gas chromatography coupled with electron capture detector GC-O-FID – gas chromatography, olfactometry and flame ionization detector GC-TOF/MS – gas chromatography time-of-flight mass spectrometry Faculty of Chemistry Adam Mickiewicz University in Poznań 8 GHG – greenhouse gas GMP – Good Manufacturing Practice HA – Hierarchical analysis of components HDPE – high-density polyethylene HPLC-DAD - high-performance liquid chromatography with diode array detector HS-SPME – headspace solid microextraction IAS – intentionally added substances ICP-MS - inductively coupled plasma mass spectrometry IUPAC – International Union of Pure and Applied Chemistry KI – Kovats Index LDPE – low-density polyethylene LLE – liquid-liquid extraction LOD – limit of detection LOQ – limit of quantification MB – mater-bi material (thermoplastic starch) NIAS – non-intentionally added substances NIR – near infrared OAV – odor activity value OECD – Organization for Economic Cooperation and Development OML – overall migration limit OT – odor threshold PAHs – polycyclic aromatic hydrocarbons PBAT - polybutylene adipate terephthalate PC – paper cup Faculty of Chemistry Adam Mickiewicz University in Poznań 9 PCA – Principal Component Analysis PCL - Polycaprolactone PCW – paper cup white PDLA – (D)-polylactic acid PE – polyethylene PET – polyethylene terephthalate PFBOA – O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine PHAs - polyhydroxyalkanoates PHE – phenanthrene PLA – polylactide cup PLB – palm leaf bowl PLLA – (L)-polylactic acid PLR – plant residues bowl PP – polypropylene PPB – black bio-polypropylene cup PP/PA – polypropylene/polyamide blend PS – polystyrene PSC – plate of sugar cane PWB – plate of wheat bran ROP – ring-opening polymerization RSD – relative standard deviation SAFE – solvent-assisted flavor evaporation SML – specific migration limit SML(T) – total specific migration limit Faculty of Chemistry Adam Mickiewicz University in Poznań 10 SUPD – Single-Use Plastics Directive TDI – tolerable daily intake TPO – diphenyl-(2,4,6-trimethylbenzoyl)phosphine oxide TS – thermoplastic starch cup 2,4-DHBP – 2,4-dihydroxybenzophenone 2-H-4-MBP – 2-hydroxy-4-metoxybenzophenone 2,2’,4,4’-THBP – 2,2’,4,4’-tetrahydroxybenzophenone US EPA – United States Environmental Protection Agency VOCs – volatile organic compounds WB – wooden bowl WTE – Waste-To-Energy Faculty of Chemistry Adam Mickiewicz University in Poznań 11 Table of contents 1. Introduction ................................................................................................................................... 13 2. Theoretical section ........................................................................................................................ 14 2.1 The global problem of fossil-based plastic waste ........................................................................ 14 2.2 Sustainable development regulations ......................................................................................... 15 2.3 New materials used as food contact materials (FCMs) ................................................................ 19 2.3.1 Characteristic of biodegradable/compostable FCMs ............................................................ 20 2.3.2 Characteristic of recyclable FCMs ......................................................................................... 21 2.3.3 Production of new FCMs ...................................................................................................... 22 2.3.4 Advantages and limitations of new FCMs ............................................................................. 26 2.4 Contamination problems in FCMs ............................................................................................... 27 2.4.1 Regulations for the served/packed food safety .................................................................... 28 2.4.2 FCMs safety assessment ....................................................................................................... 29 3. Goal and scope of doctoral dissertation ........................................................................................ 32 4. Experimental section ..................................................................................................................... 33 4.1 Analyzed FCMs ............................................................................................................................. 33 4.2 Solids and chemical reagents ....................................................................................................... 35 4.3 Apparatus and small laboratory equipment ................................................................................ 36 4.4 Research methodology ................................................................................................................ 37 4.4.1 Characteristic of food simulants used in migration studies .................................................. 37 4.4.2 Migration studies .................................................................................................................. 39 4.4.3 Different approaches in assessing the safety of food contact materials (FCMs) .................. 40 4.4.3.1 Non-targeted approach in safety assessment of food contact materials (FCMs) .......... 41 4.4.3.2 Target approach in safety assessment of food contact materials (FCMs) ..................... 41 5. Results and discussion ................................................................................................................... 60 5.1 Non-targeted approach in safety assessment of food contact materials (FCMs) ........................ 60 5.2 Targeted approach in safety assessment of food contact materials (FCMs) ............................... 64 Faculty of Chemistry Adam Mickiewicz University in Poznań 12 5.2.1 Migration study of odor-active contaminants ....................................................................... 64 5.2.2 Migration study of carbonyl compounds .............................................................................. 82 5.2.3 Migration study of high-molecular weight contaminants ................................................... 100 5.2.4 Migration study of inorganic contaminants ........................................................................ 109 6. Summary and conclusions ............................................................................................................ 124 7. References ................................................................................................................................... 126 8. List of figures ................................................................................................................................ 153 9. List of tables………………………………………………………………………………………………………………………………154 10. Scientific achievements ................................................................................................................ 155 Faculty of Chemistry Adam Mickiewicz University in Poznań 13 1. Introduction In recent years, a variety of pro-environmental regulations have been introduced in the European Union with the overarching goal of protecting and improving the environment (including the Plastics Directive; European Commission, 2019). Therefore, the packaging industry has changed the materials that are popularly used as food contact materials (FCMs) over the past few years. The promotion of the circular economy and the dissemination of environmentally friendly substitutes for fossil-based plastics began (Bhuyar, Muniyasamy & Govindan, 2018; Abu Bakar & Othman, 2019; Di Bartolo, Infurna & Dintcheva, 2021). Plant-based materials (e.g., wheat bran) and bio-based plastic (e.g., polylactide) have become dominant and are treated as “ecological materials”. They are environmentally friendly alternatives to fossil-based plastics due to their susceptibility to rapid biodegradation or reusability (Steven, Octiano & Mardiyati, 2020). Ecological materials focus on creating a more sustainable world with less environmental impact, as they decompose in an optimal time. As a result, they create biomass and environmentally friendly chemical compounds, such as carbon dioxide and water. At the same time, they have similar properties to traditional conventional materials, which largely determines the global demand for these materials (Jabeen, Majid & Nayik, 2015). However, new ecological materials can become a source of food contamination. Some of the contaminants migrating from such packaging/vessels may become from the environment, due to the natural process of sorption of environmental contaminants by plants (phytoremediation). In addition, the limited mechanical strength of ecological materials creates the need for reinforcements, such as synthetic fibers, adhesives and polymeric protective layers in the manufacturing process. They can degrade into different chemical compounds during storage or heating, which may easily migrate into the food. It can often cause undesirable changes in the quality and sensory properties of food. Therefore, the introduction of new materials on the market can be controversial. Replacing plastics with new FCMs may introduce other toxic substances that are hazardous to health and the environment (Akouesan et al., 2023). New FCMs are of various origins, which means that the number of potential contaminants that can migrate into food is constantly increasing and may still not be fully recognized. Moreover, very often materials from different production batches differ from each other. This requires constant monitoring, especially if detailed information about the material is not available from the manufacturer. Therefore, determining the safety of new, currently popular FCMs on the consumer market is a current, urgent challenge. The impact of FCMs on the amount of particularly dangerous organic and inorganic contaminants that can migrate from FCMs to food of various nature under different contact conditions should be critically assessed. Migration studies will enable a better recognition and understanding of the interactions between FCMs and food. Faculty of Chemistry Adam Mickiewicz University in Poznań 14 2. Theoretical section 2.1 The global problem of fossil-based plastic waste The invention of bakelite in 1909 by Leo Hedrik Baekeland gave rise to the polymer era (Rangel- Buitrago, Neal & Williams, 2022). The unique and desirable properties of these materials, such as lightness, transparency, ease of shaping, relatively low production cost and convenient transportation, ensured that plastics rapidly gained a global demand that continues to the present day (Nayanathara Thathsarani Pilapitiya & Ratnayake, 2024). According to Plastic Globe (2024) (Plastics Europe, 2024), global plastics production is growing year-on-year, reaching more than 413 million tonnes in 2023. The leader in global plastics production is Asia (53 %), followed by North America (17.1 %) and Europe (12.3 %). The largest sector using plastics is packaging (39.9 %). This sector has recorded accelerated growth by the global shift from reusable to disposable containers. As a result, the share of plastics in municipal solid waste (by weight) has increased from less than 1 % in 1960 to more than 10 % in 2005 in the middle- and high-income countries (Geyer, Jambeck & Law, 2017). Most used plastics (more than 370 million tonnes) are still fossil fuel-based plastics (based on oil or natural gas), which are resistant to degradation and can easily accumulate in the environment. The combination of the dynamic, uncontrolled production of such materials and the use of poorly developed waste management systems (mainly linear economy, based on actions: take-make-consume-dispose) has led to the dumping of huge amounts of waste into the environment, which can finally lead to irreversible changes (Gucina, 2023; Beghetto et al., 2023). According to Geyer et al. (2017) and Beghetto et al. (2023) over the past 65 years, more than 4,900 Mt of the 8,300 Mt of fossil-based polymers produced have been burned, pyrolyzed or dispersed into the environment, e.g., in the packaging industry about 32 % of all packaging produced has been “disposed of” in this way. Plastic waste still remains in all major ocean basins and can have toxic effects on marine biota as a global result of these activities (Yu & Singh, 2023; Tekman et al., 2023). Marine animals often mistake plastic fragments for food, leading to problems associated with ingestion, such as gastrointestinal blockages or leaching of toxic chemicals into tissues (Simon, 2022). One of the largest dumping grounds for plastic waste is the Great Pacific Garbage Patch, which was discovered in 1997 by Charles Moore (Rochman, Cook & Koelmans, 2016). The patch is currently estimated to consist of 1.8 trillion pieces of plastic (79,000 Mt) and has an area larger than Italy and Germany combined (about 660,000 km2) (Lebreton et al., 2018; Beghetto et al., 2023). Plastic fragments can form microplastics (sizes ranging from 1 µm to 5 mm) and nanoplastics (sizes less than 1 µm) in the Faculty of Chemistry Adam Mickiewicz University in Poznań 15 environment, which are harmful to living organisms due to bioaccumulation and possible absorption of hazardous contaminants (i.e., heavy metals, hormone-like molecules, hydrocarbons and dioxins) (Fred- Ahmadu et al., 2020; Gucina, 2023; Mariani et al., 2023). Contamination of freshwater systems and land habitats is also increasingly reported (Wagner et al., 2014; Dris et al., 2016). Plastic pollution degrades soil quality, disrupts nutrient cycles, plant growth and ecosystem dynamics (Dahiya, Kumar, D., Kumar, S., Pandey & Devi, 2024). The presence of hazardous polymer waste in the environment contributes to noticeable climate change, including global warming and depletion of non-renewable resources (Michelini, Moraes, Cunha, Costa & Ometto, 2017; Mora-Contreras et al., 2023). Waste that is disposed of in landfills can produce methane, a greenhouse gas with a much greater harmful impact on the environment than carbon dioxide (Ncube, Ude, Ogunmuyiwa, Zulkifli & Beas, 2021). The constantly deteriorating state of the environment has led to the recognition of the linear economic model as a driving force of unsustainable development, posing a threat to environmental security and economic development (Islam et al., 2024). 2.2. Sustainable development regulations The urgent global environmental challenges mean that the search/implementation of innovative, sustainable economic systems that meet the needs of current and future generations is currently required (FAO, 2021). The global threat of the ubiquity of plastics means that European Union (EU) directives and regulations related to the production and disposal of plastics need to address several pressing aspects. These may include product quality, emissions from industrial production, worker and consumer health, food contact requirements, recovery and recycling of post-consumer waste (Beghetto et al., 2023). Sustainability efforts include the implementation of various regulations, as presented in Fig. 1. Faculty of Chemistry Adam Mickiewicz University in Poznań 16 Fig. 1. Various regulations of the EU, introducing changes to promote sustainable development over the past two decades Faculty of Chemistry Adam Mickiewicz University in Poznań 17 One of the most important regulation was EU Directive 2019/904 (European Parliament and Council, 2019) on reducing the environmental impact of certain plastic products. It was adopted in June 2019 and entered on 3 July 2021. This document, commonly known as the Single-Use Plastics Directive (SUPD), was designed to minimize the global environmental contamination with plastic and to promote the use of reusable, biodegradable or recyclable materials. The main objective is to introduce a more sustainable and environmentally friendly economy (circular economy; CE) (Poluszyńska, Ciesielczuk, Biernacki & Paciorkowski, 2021; Uwalomwa et al., 2025). According to Beghetto et al. (2023), the environment is the basis, the economy is the tool and the well-being of society is the main goal in this economic model. The CE concept is derived from various ideologies that have evolved over the past decades (Uwalomwa et al., 2025). The first mentions of sustainability and pro-environmental practices appeared in 1966 in the work of Kenneth Boulding (Boulding, 1966), who emphasized the depletion of natural resources in the environment and pointed to the need for sustainable development practices and a circular economy system. The industrial ecology movement of the 1970s and 1980s (Rosenboom, Langer & Traverso, 2022), which launched the term “industrial ecology”, was also an important development in the field. The main motive was to design industrial systems that would reflect the functioning of natural ecosystems (Frosch & Gallopoulos, 1989). The term “circular economy" was officially introduced in 1976 by the European Commission, based on the work of Walter Stahel and Genevieve Reday-Mulvey (Stahel & Reday-Mulvey, 1981). The global popularity of the CE concept is due to the work of the Ellen MacArthur Foundation since 2010. Its main goal is to accelerate the transition of the global economy to CE. Since its inception, the foundation has become a global leader in CE and collaboration between academia, business and government in this area. CE is a model of sustainability that aims to reduce waste and increase resource use. CE focuses on closed systems that promote the reuse, repair, remanufacturing and recycling of goods, materials and resources (Kirchherr et al., 2018). The basic principles of the closed-loop economy model are based on maximizing the value of resources used, reusing production and consumption waste and pursuing renewable energy sources (Didenko, Klochkov & Skripnuk, 2018; Geissdoerfer, Morioka, Carvalho, Evans, 2018; Moshood et al., 2022). This creates a material-energy cycle in the economic system that considers the closed cycle of goods (Fig. 2). The initial 3R principles (reduce, recycle, reuse) have evolved into a more comprehensive 9R framework, including reject (R0), rethink (R1), reduce (R2), reuse (R3), repair (R4), refurbish (R5), remanufacture (R6), reuse (R7), recycle (R8) and recover (R9) to enhance corporate responsibility and facilitate a smoother transition to CE (Islam et al., 2024). Faculty of Chemistry Adam Mickiewicz University in Poznań 18 Fig. 2. Flow chart of the circular economy The formation and functioning of circular economy are supported by various approaches. The first one is the design and production in accordance with the “cradle to cradle” philosophy. This means considering the entire life cycle of products and promoting the use of materials that can be safely reintegrated into the environment or continuously reused in industrial processes (Uwalomwa et al., 2025). The second approach is the concept of the restorative economy, which emphasizes the need to protect and enhance natural resources and encourages economic activities that contribute to environmental regeneration and sustainable development (Stahel, 2016). The third approach concerns natural capital accounting, which integrates the value of natural resources and ecosystem services in financial statements. This helps companies understand their impact on the environment and make informed decisions about the use of resources (Uwalomwa et al., 2025). According to Jaworski and Grochowska (2017), the product design stage is crucial for meeting the main CE assumptions. The product and its entire life cycle are shaped at this stage. The use of practices and tools such as resource saving, eco-design, life cycle assessment and eco-labelling can ensure compliance with the CE idea. The production stage is associated with the extraction and processing of resources, which requires energy input and generates large amounts of waste, especially in highly developed companies. Fulfilling the CE principle at this stage can be particularly difficult. It is important to meet Good Manufacturing Practice (GMP) principles, strive to improve the efficiency of technological processes and introduce innovative solutions using tools such as the environmental technology Faculty of Chemistry Adam Mickiewicz University in Poznań 19 verification system (ETVS), the eco-management and audit system (EMAS) and the environmental footprint. The product use stage is associated with consumerism. It requires ecological awareness of society and promotion of pro-ecological attitudes. The product should be used in the most effective way, which will contribute to minimizing excessive consumption. The final stage is waste management and activities are focused on waste prevention and promoting recycling (waste can be recovered and reintroduced into circulation and used in the next cycle). Waste that is not suitable for recycling should be subjected to other recovery processes (incineration and co-incineration of waste), which allow for a high level of energy recovery and processing of waste into solid, liquid or gaseous fuels. The least desirable form of waste management is its neutralization (wasting potential), which includes waste storage in landfills and thermal processing of waste without significant energy recovery. A global popularization of new materials in the packaging sector is currently observed in order to achieve the above-mentioned, main objectives of sustainable development. 2.3 New materials used as food contact materials (FCMs) Sustainable development strategies (mainly the CE approach) and society’s concern for the environment makes it necessary to introduce changes in the packaging sector. Research is currently underway to find alternative materials with functional properties similar to fossil-based plastics, but safe for the environment. In general, all materials used in packaging can be divided in terms of renewable resources and biodegradability, as presented in Fig. 3. Fig. 3. Division of materials based on renewable resources and biodegradability (adapted from European Bioplastics, Bioplastic Materials, 2020; (the abbreviations used are explained in the List of Symbols) Faculty of Chemistry Adam Mickiewicz University in Poznań 20 The most desirable are “double green” materials, which are produced from renewable resources and are biodegradable (so-called plant-based materials and bio-based plastics) (Barbale et al., 2021). Another important area of research is the search for methods to increase the recycling rate of non- biodegradable polymers obtained from fossil raw materials. These measures will reduce the use of natural resources. Global demand for more environmentally friendly materials has led to an increase in the production of these materials and is expected to continue to grow in the next few years. According to Plastic Globe (Plastics Europe, 2024), global production of “ecological materials” was almost 40 million tons (about 10 % of global plastic production) in 2023. More than 36 million tons include recyclable materials and about 3 million tons were bio-based plastics. Between 2018 and 2023, production of such materials increased by more than 8 million tons. 2.3.1 Characteristic of biodegradable/compostable FCMs Based on the definition proposed by the International Union of Pure and Applied Chemistry (IUPAC), bio-based plastics are materials derived from “biomass or monomers derived from biomass and which, at some stage in its processing into finished products, can be shaped by flow” (McNaught & Wilkinson, 1997). Such bio-based plastics contain natural polymers or salt mixtures that biodegrade much faster than traditional plastics. Biodegradable plastics are considered environmentally friendly because they are produced from renewable agricultural materials (Lomwongsopon & Varrone, 2022). They contribute to the conservation of limited natural resources. Biodegradation is the process of decomposition of plastics under the activity of microorganisms (bacteria, fungi, algae) under certain environmental conditions into natural chemical compounds (biomass, water and carbon dioxide). This reduces the impact of such materials on ecosystems (especially marine) and human health. Furthermore, the production of bio-based plastics and biomaterials often requires less energy, thus reducing greenhouse gas (GHG) emissions (Mahmoud, Yasien, Swilam, Gamil & Ahmed, 2023). The biodegradation process of plastics depends on many factors, which are summarized in Fig. 4. Faculty of Chemistry Adam Mickiewicz University in Poznań 21 Fig. 4. Factors influencing the rate of the biodegradation process Plastics that biodegrade quickly and under well-defined conditions are called compostable polymers. This means that under controlled composting conditions, 90 % of the plastic degrades within six months and the compost produced is not harmful to plants. In many countries (e.g., Italy), biodegradable bio-based plastics certified as compostable (based on EN 13432:2000) are collected with biowaste and processed in anaerobic digestion (AD) plants and composting facilities. According to Cucina et al. (2022), the circularity of biosolids is particularly enhanced in AD systems, where they can be converted to biogas, generating a corresponding amount of renewable energy and reducing their release to the environment. 2.3.2 Characteristic of recyclable FCMs The global waste management market was estimated to cost at USD 1,293.70 billion in 2022 and is expected to grow at a compound annual growth rate (CAGR) of 5.4 % from 2023 to 2030 (Report ID: GVR-4-68039-917-8). In Europe, 23 million tons of plastic packaging are produced per year and current forecasts predict 92 million tons by 2050 (Guillard et al., 2018; Ncube et al., 2021). However, recycling rates for single-use plastic packaging are currently low. According to Ncube et al. (2021), only 14 % of Faculty of Chemistry Adam Mickiewicz University in Poznań 22 plastic packaging is collected for recycling and 5 % is successfully recycled into new plastic. The planned EU packaging waste targets are related to ensuring that 75 % of packaging is recycled by 2030. Therefore, increasing the efficiency of recycling and upcycling of plastic waste is crucial. Recycling can reduce the consumption of raw materials and reduce waste through a closed loop. Upcycling is the addition of value to plastic waste to produce a higher value product (Jung et al., 2023). The effectiveness of recycling and upcycling depends on the functioning of the several system elements, which can include: - appropriate legislative policies to promote recycling and the development of waste treatment technologies, - the design of goods consisting of homogeneous materials sent for recycling, which facilitate waste separation, - the design of products consisting of different materials that will be easily separable, - the design of goods allowing waste to be stored and reused without treatment (or with minimal treatment), - proper labelling of packaging and product components, which facilitates recognition and proper segregation of waste. 2.3.3 Production of new FCMs FCMs made of renewable raw materials (plants) are increasingly appearing on the consumer market, due to environmental concerns. The most commonly used plant-based FCMs include sugar cane fiber (bagasse), wheat bran, palm leaves, wood and others. In general, the production technology of plant-based FCMs is based on the initial cleaning of the raw material, soaking, drying and extrusion of the desired shapes (usually using pressure extrusion). Plants are also used as primary raw materials for obtaining polysaccharides (Fig. 5). Faculty of Chemistry Adam Mickiewicz University in Poznań 23 Fig. 5. Main stages of production of plant-based and bio-based plastics FCMs Starch is a key component in the production of biodegradable (and compostable) plastics due to its cost-effectiveness and ease of processing. This raw material has found wide application in packaging Faculty of Chemistry Adam Mickiewicz University in Poznań 24 (Matheus et al., 2023; Garavito, Peña-Venegas & Castellanos, 2024; Haq et al., 2025). Starch can be extracted from cassava, corn, potatoes and beans. It is a natural, crystalline polysaccharide and occurs in the form of grains. The production of starch packaging/vessels involves its decomposition (destructuring) and chemical modification, such as etherification or esterification. These processes aim to improve the mechanical properties, water resistance of starch and compatibility with other polymers (Kim & Jung, 2022). Plasticizers (e.g., sorbitol, glycerol) are also often added at the production stage to improve the mechanical properties of starch-based products (e.g., increase elasticity) (Kshirsagar & Shinde, 2023). The whole is subjected to the action of thermal and mechanical energy, resulting in the formation of thermoplastic starch (TS), which can be considered a substitute for polystyrene (PS). Starch is most often used for the production of films characterized by high tensile and bending strength. The degradation time of starch products in conventional composting plants is 20-45 days (Fazal et al., 2025). Another natural polymer is polylactide (PLA) composed of many connected 2-hydroxypropanoic acid molecules. This aliphatic polyester is produced by fermentation of starch-rich agricultural by- products (e.g., potatoes, corn, wheat). There are three known routes for the synthesis of PLA: direct condensation polymerization, azeotropic dehydration condensation and ring-opening polymerization (ROP), which is the most commonly used, although it requires purification and the use of heavy metal catalysts (Singhvi, Zinjarde & Gokhale, 2019; Li et al., 2020; Oliver-Cuenca et al., 2024). Several methods are used to process PLA, including extrusion, injection molding, thermoforming and foaming (Castro-Aguirre, Iñiguez-Franco, Samsudin, Fang & Auras, 2016). Thermoforming is most commonly used in the production of FCMs. The process involves heating PLA to soften it, then using compressed air and pressing the material into the mold. The properties of PLA depend on the ratio between the two optical isomers of the lactic acid monomer (PLLA and PDLA). In order to improve functional properties and flexibility, PLA is often blended with plasticizers (glycerin, polyethylene glycol or vegetable oils) (Carbonell-Verdu et al., 2017). PLA can be considered as an ecological substitute for high-density polyethylene (HDPE), low-density polyethylene (LDPE), polyethylene terephthalate (PET) and polystyrene (PS). PLA is subjected to microbial degradation. In strictly defined environmental conditions, enzymes produced by microorganisms (e.g., lipases, proteases) can catalyze the hydrolysis of PLA chains. PLA, under the right conditions, degrades within 80 days (Oliver-Cuenca et al., 2024). In turn, cellulose has been widely used in the production of recyclable paper products. Cellulose fibers can be recovered from wastepaper and further processed into new products (Copenhaver et al., 2021; Wang et al., 2021; Fazal et al., 2025). Cellulose is obtained from trees, cotton and sugar cane stalks. It is a tasteless and odorless solid. It has a linear structure formed from β-D-glucopyranose Faculty of Chemistry Adam Mickiewicz University in Poznań 25 molecules connected by β-(1,4)-glycosidic bonds. Subsequent layers of the chain overlap, which results in the formation of fibers stabilized by hydrogen bonds. This gives the entire structure a very high durability and creates major problems in polymer processing. High chemical and mechanical strength cause poor solubility in water and organic solvents. Therefore, it is necessary to modify cellulose into water-soluble derivatives to obtain paper. For this purpose, an esterification reaction is carried out, which produces cellulose ethers and esters (i.e., cellulose acetate). Cellulose packaging is often reinforced with synthetic polymer films (e.g., polyethylene (PE)). According to Fazal et al. (2025), the process of producing cellulose vessels is environmentally friendly, as it causes the emission of about 0.2 kg CO2/kg of material (for comparison, the production of PS produces 7.4 kg/kg of material, respectively). On the other hand, recycling materials involves several important steps that impact a sustainable approach to waste management. First, the efficiency of the recycling and the final product is highly dependent on the initial collection and sorting stages, as the quality of the input material has a strong influence on the efficiency of the waste management and material recovery process. Therefore, many techniques have found widespread application in this field, such as near infrared (NIR) (Cimpan, Maul, Jansen, Pretz & Wenzel, 2015), Fourier transform infrared, ultrasound, laser-induced breakdown spectroscopy or X-ray fluorescence (Rahimi & García, 2017; Singh et al., 2017). Currently, plastics are recycled mechanically and chemically. The first one (also called secondary recycling) is for homogeneous waste with a low degree of contamination and consists of the following steps: I) the recycled plastics have to be separated from the non-plastic components and then the different plastics are collected separately using optical, manual, floating/sinking techniques, II) grinding and milling – common polymers and/or additives can be added to the recycled material, III) extrusion – the efficiency of polymer recycling depends on the sorption properties and inertness of the polymer and the diffusion behavior of the polymer. FCMs produced from transparent polymers (PET and HDPE) are suitable for recycling in this way, while HDPE is susceptible to sorption of contaminants (Clark, Jung & Lamsal, 2014). Mechanical recycling is mainly implemented in developing countries because it is a low-cost and efficient process. However, this process has some limitations because with each successive recovery cycle the material loses its quality. Chemical recycling (also called raw material recycling) is the decomposition of polymers in a controlled manner into monomers and oligomers by chemical reactions such as pyrolysis, hydrogenation, hydrolysis and hydrocracking. Chemical recycling is considered as a Faculty of Chemistry Adam Mickiewicz University in Poznań 26 complementary strategy to mechanical recycling and allows to increase the percentage of recycled plastic waste (Huang, Veksha, Chan, Giannis & Lisak, 2022). Another form of recycling is energy recovery, which is based on waste incineration and recovery of heat and electricity. Energy sources are mainly plastics from crude oil, which are characterized by high calorific value, e.g., for polyethylene and polypropylene they are about 45 and 46.5 MJ/kg, respectively, while the calorific value of crude oil is about 42.5 MJ/kg (Panda, Singh & Mishra, 2010). Incineration reduces the volume of waste by about 99 %, but on the other hand it can contribute to the emission of harmful chemical compounds into the environment (this requires air quality control) (Ferronato & Torretta, 2019). Popular methods of waste-to-energy (WTE) used in developed countries are divided into thermal (pyrolysis, incineration and gasification), chemical (esterification) and biochemical (fermentation) (Rafey, Prabhat & Samar, 2020). Currently, the efficiency of electricity generation using WTE technology is about 80 %. Modern incinerators are equipped with state-of-the- art air pollution control technologies to minimize emitted air pollutants (Al Qattan et al., 2018; Hahladakis, Velis, Weber, Iacovidou & Purnell, 2018). 2.3.4 Advantages and limitations of new FCMs The current poor state of the environment requires major changes in the packaging sector. Regulations promote investment in bio-based plastic, plant-based and recyclable material technologies, which increases market demand (Moshood et al., 2021). Filho et al. (2021) suggest that most consumers are aware of the problem of plastic pollution and are committed to reducing plastic consumption by using sustainable alternatives to fossil-based plastics. According to Mousavi et al. (2024), Mohery, Mindil and Soliman (2024), Fazal et al. (2025), the implementation of biodegradable and recyclable materials presents challenges and opportunities. Significant opportunities include reducing pollution, promoting sustainable material alternatives and supporting new recycling technologies. However, key challenges are related to high production costs (compared to conventional plastics) and the need to improve waste management infrastructure. It has been estimated that the production of about 1 kg of bio-based plastic requires about 1-2 kg of corn or about 5-10 kg of potatoes, which may result in deforestation of the crops used to produce these materials (Jeremic, Milovanovic, Mojicevic, Bogojevic & Nikodinovic-Runic, 2020). Moreover, plastics recycling processes are difficult to implement. Most plastics (more than 50 % of waste) are produced from olefins (e.g., LDPE, HDPE, PP) (Vieyra, Molina-Romero, Calderon-Najera & Faculty of Chemistry Adam Mickiewicz University in Poznań 27 Santana-Diaz, 2022). Their structure consists of polymer chains with strong covalent C-C bonds. This makes their decomposition require high energy inputs and the use of high-performance catalysts (Jung et al., 2023). Therefore, the recycling rate of olefin-based polymers is currently low at less than 10 % (Chaudhari et al., 2021). Some plastics (e.g., PET) are more given to reuse, as there is an ester bond in their structure that is susceptible to decomposition by hydrolysis. However, PET waste currently accounts for about 10 % of all plastic waste generated. Mixtures of plastics that are combined within a single product are also a major limitation, making the sorting efficiency of such waste low (Roosen et al., 2020; Vogt, Stokes & Kumar, 2021; Jung et al., 2023). Furthermore, the use of a wide range of new materials as food contact materials (FCMs) may raise food safety concerns. 2.4 Contamination problems in FCMs Food contact materials (FCMs) are an important element of packaged/served food because they fulfill various functions, i.e., protection, information, marketing and logistics (Kato & Conte-Junior, 2021). However, not every material can be used as a FCMs, because they must comply with basic food safety requirements (European Commissions, 2011, 2018). This means that FCMs should be manufactured in compliance with GMP principles in order to limit transfer contaminants into food that could adversely affect human health or cause unacceptable changes in the composition or properties of foodstuffs (Commission Regulation, 2006). However, since the 1970s and 1980s, some researchers have reported that the phenomenon of migration of various contaminants from packaging materials (conventional plastics) can significantly reduce the quality of food and change its sensory profile (Figge & Koch, 1973; Senich, 1982; Taverdet & Vergnaud, 1984; Scriven, Sporns & Wolfe, 1987). The packaging material is often reinforced and enriched on the production line by adding various chemical compounds that improve the final properties of FCMs, such as light, oxidation and impact resistance, appropriate hardness and the others (Rodrigues et al., 2019; Kato & Conte-Junior, 2021; Fengler & Gruber, 2022; Lerch, Fengler, Mbog, Nguyen & Granby, 2023; Phelps, Parkinson, Boucher, Muncke & Geueke, 2024). This means that interactions between FCMs and food require monitoring and control to assess the safety of popular FCMs. Faculty of Chemistry Adam Mickiewicz University in Poznań 28 2.4.1 Regulations for the served/packed food safety Interactions that occur between FCMs and food can lead to significant changes in the quality and sensory properties of food. The most undesirable changes may be caused by the bidirectional migrations. This phenomenon occurs mainly with molecularly dispersed low-molecular-weight substances, which can be easily transferred from FCMs to food and conversely (Kato & Conte-Junior, 2021). Based on the Fick's law, it can be assumed that the migration of substances occurs by diffusion between media of different concentrations, until an equilibrium state is established (Kato & Conte- Junior, 2021; Wang, Gao, Liu, Lin & Xia, 2020). In general, the stages of migration can be divided into desorption of dispersed molecules from the surface of FCMs, sorption of compounds at the FCM-food interface and desorption of compounds in food (Bhunia, Sablani, Tang & Rasco, 2013; Schmid & Welle, 2020). Regulating the safety of served/packaged food requires the establishment of appropriate supervisory authorities, which is globally presented in the Fig. 6. Fig. 6. FCM safety regulators around the world In the EU, the European Food Safety Authority (EFSA) operates, which is an advisory body to the legislator (Commission) in terms of authorizing permitted substances added to plastic products (risk assessment). On the other hand, the European Commission establishes regulations on FCMs. One of the Faculty of Chemistry Adam Mickiewicz University in Poznań 29 most important regulations in this area is Regulation (EU) No. 10/2011 (amendment on September 23, 2020), which applies to materials and articles intended for contact with food, made of plastics. Annex I of this regulation contains a positive list (the so-called Union list) of substances (including monomers, auxiliary agents, macromolecules produced by microbiological fermentation and others) that are permitted as intentional additives used in the production process of plastic materials and products. Although no specific regulations have been established for the use of other, currently popular FCMs yet, controlling their safety is subject to the same regulations as plastics. 2.4.2 FCMs safety assessment The safety assessment of FCMs consists of several steps, which are summarized in Fig. 7. Fig. 7. FCM safety assessment steps Prediction and migration tests are conducted to assess the impact of FCMs on the quality and sensory properties of food, in accordance with Commission Regulations (No. 10/2011; No. 213/2018 and No. 1245/2020). The contact time and temperature between the vessel/packaging material and the food should reflect the worst possible conditions (highest temperature and longest time), e.g., if the FCM is intended for short-term contact with hot food, then the migration test conditions of 2 h and 70°C are used. The detection and identification methods depend on the substance that can migrate from FCMs to food (so called food contact substances (FCS)). They can be defined as “any substance intended for use as a component of materials used in the production, packaging, transportation or storage of food, where such use of the substance is not intended to have any technical effect on such food.” (Bhunia et Faculty of Chemistry Adam Mickiewicz University in Poznań 30 al., 2013; Kato & Conte-Junior, 2021). FCS are divided into intentionally added substances (IAS) or non- intentionally added substances (NIAS). The sources of their migration are several, as presented in the Fig. 8. These may include: I) antioxidants and UV stabilizers – are added to many FCMs to protect them from photo- or thermo- oxidation, II) antistatic agents – prevent the accumulation of electric charges on the surface of plastics, which facilitates the packaging process and prevents dusting, III) plasticizers – ensure the appropriate flexibility and strength of FCMs, IV) slip agents – facilitate mechanical packaging, V) by-products compound – production of starting substances, materials, additives and food packaging side reactions can occur, which lead to new, often unknown products, VI) degradation products – may be formed as a result of thermal decomposition of polymers; decomposition products are the main source of NIAS in FCM. Degradation of polymers and additives leads to the formation of new low molecular weight substances that can easily migrate into food, VII) contaminants from the raw material – these can be any substances left over from the production process, e.g., residues of catalysts, solvents, paints; in the case of plant raw materials, these can also be contaminants adsorbed by the plant during its growth from a polluted environment (phytoremediation process). The processes of migration of various chemical compounds from FCMs to food can lead to undesirable changes in the physicochemical properties of food (Groh et al., 2019; Kato & Conte-Junior, 2021). Fig. 8. Examples of intentionally and non-intentionally added substances (IAS and NIAS, respectively) in FCMs that can easily migrate into served/packaged foods Faculty of Chemistry Adam Mickiewicz University in Poznań 31 IAS are included in the positive list of the European Commission, 2011. The specific migration limit (SML) has been established for each IAS which allows for the assessment of the migration level and consumer exposure. SML determines the maximum concentration of undesirable chemical compounds that can be identified in food (mg/kg food or µg/g of food). However, the presence of NIAS may pose the greatest concern for food safety, mainly due to the not fully understood and spontaneous mechanisms of formation of such substances (Wrona & Nerín, 2020). Although it is impossible to establish an SML for them, they are subject to an overall migration limit (OML). This parameter represents the general limit of FCM inertness and is established on the basis of gravimetric measurements. The OML determines the sum of all substances migrating from the analyzed FCMs under test conditions (for non-volatile compounds, it must not exceed 10 mg/dm2 FCM or 60 mg/kg of food). Based on the determined concentrations of migrating organic and inorganic contaminants, the safety of FCMs can be assessed, which is the final conclusion of the FCMs safety assessment. The increasing popularization of new plant-based FCMs and bio-based plastics FCMs, has raised questions about their safety and impact on food. To date, there are still few literature reports on the safety of new plant-based raw materials, such as wheat bran, palm leaves, bamboo, sugarcane, wood, plant residues and bio-based plastics. This is an important research gap, because these materials can have particularly effect of food quality. Plant raw materials may contain various environmental contaminants. The natural ability of plants to biodegrade, accumulate and inactivate substances from the environment means that dangerous chemical compounds can be stored in their tissues. Moreover, toxic chemical substances may be produced by plants as secondary metabolites in response to environmental stresses, e.g., during shearing. An additional source of contamination is the bio-based plastic FCM production process, in which various NIAS can enter FCMs through cross-contamination. Therefore, the global production of new FCMs may become a serious food contamination problem and cause controversy. This issue is important, especially nowadays, when there are changes in food trends and a clear focus on: smaller packages with larger food contact surfaces, more processed foods with long shelf life and packaged heated products. Additionally, the group of people potentially exposed is also increasing due to the spread of new FCMs in fast food bars, restaurants, schools and hospital canteens. Faculty of Chemistry Adam Mickiewicz University in Poznań 32 3. Goal and scope of doctoral dissertation The research objective of the dissertation is to comprehensively characterize the bidirectional interactions occurring between plant-based and bio-based plastics food contact materials (FCMs) and food or food simulants (imitating foods of different nature). The realization of this objective includes conducting migration studies under well-defined conditions (based on current regulations), which will allow assessing the impact of currently popular FCMs on the sensory profile and safety of foods. In the first part of the study, a wide spectrum of different groups of chemical compounds that can easily migrate from FCMs to food was determined (non-targeted analysis). On this basis, the scale of diversity of the FCMs studied was assessed and targeted analyses presented in the second part of the study were designed. Targeted analyses enabled the assessment of the impact of the FCMs studied on the sensory profile of food, the selection of markers for assessing the impact of various factors on the intensity of migration processes and the assessment of the impact of new, popular FCMs on food quality and safety. The research assumptions allow to formulate the following research theses: - the materials analyzed differ in terms of contaminants released into food depending on their origin, - volatile contaminants of low molecular weight can be easily released from FCMs, therefore they can be successfully used as markers to assess the effect of different factors on the intensity of FCMs- food interaction, - plant-based FCMs can specifically alter the sensory profile of food, - some hazardous compounds can migrate from FCMs into food at concentrations exceeding the specific migration limits (SML) or tolerable daily intake (TDI). Faculty of Chemistry Adam Mickiewicz University in Poznań 33 4. Experimental section 4.1 Analyzed FCMs Commercially available plant- and bio-based plastics FCMs were analyzed. A description of vessel material details with the corresponding photo is presented in Table 1. In addition to the presented FCMs, glass (GLA) was used as a reference material in some migration studies. Table 1. Description of the tested FCMs Type of FCM Abbreviation of the sample name Average weight of the entire vessel (n=10) [g] Plate of wheat bran PWB 97.3 Palm leaf bowl PLB 10.8 Bamboo bowl BAM 5.1 Plate of sugar cane PSC 10.6 Faculty of Chemistry Adam Mickiewicz University in Poznań 34 Wooden bowl WB 1.5 Plant residues bowl PLR 10.3 Polyethylene coated paper cup PC 13.2 Paper cup (white) PCW 7.5 Polylactide cup PLA 4.5 Bio- polypropylene cup BIOPP 2.8 Thermoplastic starch cup TS 3.0 Faculty of Chemistry Adam Mickiewicz University in Poznań 35 Expanded polypropylene bowl EPP 12.9 Black bio- polypropylene bowl PPB 9.8 4.2 Solids and chemical reagents The chemical reagents that were used during the research tasks are presented in Table 2. Table 2. List of solids and solvents Solids / Solvents Company Product Specification O-(2,3,4,5,6- pentafluorobenzyl)hydroxylamine hydrochloride Merck Ltd. LiChropur™, purity ≥ 99.0 % Tenax Matrix Tenax® TA, 60-80 mesh, bottle of 10 g Standards of analytes (see Tables 6 and 11) Merck Ltd. Analytical standards Multielement Calibration Standard 3- 10 mg/L in 5 % HNO3 (CAS 7697-37-2) Perkin Elmer Pure Plus Analytical standards ICP Standards: Ge and Rh 1000mg/L Merck Ltd. CertiPure Anhydrous Sodium Chloride Avantor Performance Materials Poland S.A. Purity ≥ 99.5 % Anhydrous Magnesium Sulfate Chempur® Purity ≥ 99.0 % Absolute Ethanol Merck Ltd. Absolute for analysis EMSURE® ACS, ISO, Reag. Ph Eur Anhydrous Acetic Acid Glacial, ReagentPlus®, purity ≥99 % Faculty of Chemistry Adam Mickiewicz University in Poznań 36 Hexane Suitable for HPLC, LiChrosolv®, purity ≥ 98 % (GC) Sulphuric acid Suprapur® Methanol Gradient grade, suitable for HPLC, LiChrosolv®, reag. Ph. Eur., purity ≥99.9 % (GC) Dichlorometane Puriss. p.a., ACS reagent, reag. ISO, purity ≥ 99.9 % (GC) 63 % nitric acid Trace Metal Grade Suprapur® 30 % Hydrogen peroxide (Perhydrol TM) for analysis EMSURE® ISO Acetone P.P.H. “STANLAB” Sp. j. Purity ≥ 99.0 % 4.3 Apparatus and small laboratory equipment Apparatus and small laboratory equipment that were used during the research tasks are presented in Table 3. Table 3. Summary of apparatus and small laboratory equipment Type Producer GC-TOF/MS Agilent 7890&7820 GC-O-FID Hewlett 5890, Packard Series II, Wilmington, DE, U.S.A. GCxGC-TOF/MS Pegasus 4D, LECO, St. Joseph, MI GC-ECD Fisons Series 8000 GC GC-FID HEWLETT PACKARD 5890 SERIES II HPLC-DAD Agilent 1100 Series ICP-MS Agilent 7700x Spring 25 demineralizer HLP Hydrolab Poland Laboratory drying oven POL-EKO-APARATURA, SLW 53, 115, 240, 400, 750, 1000; SLN53, 115, 240. Version 3.0 Faculty of Chemistry Adam Mickiewicz University in Poznań 37 Magnetic heating stirrers VWR®, VMS-C4 Advanced Centrifuge UNIVERSAL 320, HETTICH Z IKA KS 130 shaker Merck Ltd. SAFE with heating controller (ESM-3711-H) and vacuum (T-Station85) Laboplay; Edwards Lifesciences Poland Sp. z o.o. Kuderna Danish concentrator Merck Ltd. Microwave oven LG; MS-1042G Autosorb iQ Station 1 port transducer Quantachrome® ASiQwin™ Automatic Gas Sorption Data Acquisition and Reduction ©1994-2013, Quantachrome Instruments version 3.01. Rotary Vacuum Evaporator RVO 200A INGOS s.r.o. Ball mill Mini-Mill Pulverisette 23, Fritsch, Germany High Performance Microwave Digestion System ETHOS ONE, Italy Small laboratory equipment, i.e., cellulose thimbles, reflux condenser, desiccator, SPME fiber, pipettes, volumetric flasks, conical flasks, round-bottomed flasks (100 ml), vials, chromatographic needles (1 µl; 5 µl) and columns, Petri dishes, teflon vessels and others Merck Ltd.; Alchem Group Ltd.; LaboService 4.4 Research methodology 4.4.1 Characteristic of food simulants used in migration studies It is complicated and analytically challenged to conduct IAS and NIAS migration studies from FCMs to real food due to the complex composition of the food. Therefore, food simulants are commonly used in migration studies to simplify control processes. Each of the food simulants represents a different type of food (Regulation (EU) No. 10/2011) (Table 4). Faculty of Chemistry Adam Mickiewicz University in Poznań 38 Pure water was obtained by distilling tap water in a Spring 25 demineralizer (HLP Hydrolab Poland). Ethanol solutions of appropriate concentrations (10 %, 20 % and 50 % v/v) were obtained by diluting absolute ethanol. Similarly, 3 % acetic acid was obtained by diluting glacial acetic acid. Preparation of Tenax for migration studies was carried out similarly to the procedure described in the works (Rubio, Sarabia & Ortiz, 2018; Rubio, Valverde-Som, Sarabia & Ortiz, 2019) with the following modifications. Five g of Tenax was placed in a cellulose thimble and purified with 70 ml of methanol using a reflux condenser for 6 hours before use. The food simulant was then heated to 160°C for 6 h using laboratory drying oven and stored in a desiccator. Tenax was mixed to homogenize the material before migration studies. Table 4. List of food simulants commonly used in migration studies (in accordance with Regulation (EU) No. 10/2011) Symbol of food simulant Name of food simulant Type of simulated foods Example of simulated foods A 10 % ethanol / water Neutral foods Mineral waters, honey B 3 % acetic acid Acidic foods Vegetable soups, fruit juice C 20 % ethanol Alcoholic foods Wine, bear D1 50 % ethanol Lipophilic foods containing more than 20% alcohol and oil-in- water emulsions Milk and milk-based drinks, whole, partially dehydrated and skimmed or partially skimmed E Tenax Dry and frozen foods Pasta, groats, rice, ice cream Faculty of Chemistry Adam Mickiewicz University in Poznań 39 4.4.2 Migration studies The migration studies were performed depending on the type of food simulant used. The analyzed FCMs were weighed, cut into equal pieces (1 cm × 1 cm) and extracted with 200 ml of properly liquid food simulant (A: 10 % EtOH, distilled water; B: 3 % acetic acid; C: 20 % EtOH and D1: 50 % EtOH) in 70°C for 2 h (in accordance with the recommendations of Commission Regulation (EC) No 10/2011). Temperature stability over time was achieved using magnetic heating stirrers with temperature control function (Fig. 9 I). One sample contained half of the original weight of the vessel, assuming that half of the material is in contact with food at meal time. After the migration tests, the material was separated from the simulant (filtered and centrifuged). Four g of Tenax per 1 dm2 of surface was used in migration tests, according to the guidelines (Commission Regulation (EU) No 10/2011). The analyzed materials were cut into pieces measuring 5 cm x 5 cm (the surface was 25 cm2), placed on watch glasses and covered with one g of Tenax (Fig. 9 II). The sample was wrapped in aluminum foil (to eliminate the possibility of evaporation) and placed in an oven heated to 70°C for 2 hours or to 40°C for 10 days, which corresponds to short or long contact conditions between food and the vessel (Commission Regulation (EU) No 10/2011). In next step, Tenax was extracted twice with 25 mL of extractant (acetone or methanol) within 1 h at ambient temperature. The extracts were concentrated to 4 mL by vacuum evaporation (p = 850 hPa) and placed in amber glass vials. Blank samples were prepared for all analysis in the same way as tested samples, but without the use of FCMs. Three replicates were performed for each sample and blanks. I Faculty of Chemistry Adam Mickiewicz University in Poznań 40 II Fig. 9. Migration studies of various contaminants from analyzed FCMs to (I) liquid food simulants and (II) Tenax 4.4.3 Different approaches in assessing the safety of food contact materials (FCMs) Currently observed global environmental pollution (air, water, soil) may affect the contamination of primary raw materials used for the production of food contact materials. In turn, improving the functional properties of new FCMs requires the use of additives and enhancers on the production line. As a result of FCM-food interactions, food may be contaminated with various groups of chemical compounds (organic and inorganic) that may come from the environment or the production line. Therefore, the evaluation of FCMs-food interactions was carried out on a wide group of different, currently popular FCMs. Due to the large diversity of the FCMs studied (plant materials, paper, bio- based plastics), a non-targeted and a targeted approach were used to qualitatively and quantitatively assess the migrating contaminants (intentionally added substances – IAS and non-intentionally added substances – NIAS). The first approach is intended to group migrating contaminants (e.g., into more- toxic-less-toxic, organic-inorganic, volatile-non-volatile, odor active-odorless, etc.) from FCMs into different food simulants under test conditions. This makes it possible to compare, evaluate and predict the effects of FCMs on food simulant (food). It also allows for selecting FCMs that may pose a particular risk to food and therefore require detailed control. In addition, the non-targeted approach simplifies the selection of markers for targeted analyses. In turn, the targeted approach enables quantitative assessment of monitored organic and inorganic contaminants (IAS and NIAS) and comprehensive assessment of the impact of various FCMs on the sensory profile and quality of the food simulant, using appropriately selected analytical, statistical Faculty of Chemistry Adam Mickiewicz University in Poznań 41 and sensory methods. It enables searching for the causes of differences in the intensity of FCMs-food interactions, depending on the type of FCMs, type of food and other factors. 4.4.3.1 Non-targeted approach in safety assessment of food contact materials (FCMs) Intentionally added substances (IAS) and non-intentionally added substances (NIAS) in food samples were detected using GC/TOF-MS (Agilent 7890&7820). Compounds were determined using a capillary column coated with SLB-5MS phase (30 m × 250 μm i.d., 0.25 μm film thickness). One microliter of samples was injected in split/splitless mode. The initial oven temperature was held at 40°C for 2 min, ramped to 280°C at a rate of 9°C /min and held for 4 min. Helium was used as a carrier gas at a constant flow rate of 1 mL/min through the column. The temperatures of the front inlet, transfer line and electron impact ion source were set at 250, 280 and 230°C, respectively. The ionization energy was 70 eV. The mass spectral data was collected in a full scan mode (m/z 33–333) and in selected ion monitoring mode. Acquisition delay was 240 sec, rate was 30 spectra/sec and extraction frequency were 30 kHz. Principal Component Analysis (PCA) was used to determine the groups of key compounds migrating from currently popular FCMs into food using SIMCA software. 4.4.3.2 Target approach in safety assessment of food contact materials (FCMs) Intentionally added substances (IAS) and non-intentionally added substances (NIAS) that may migrate from FCMs to food can include toxic elements, which can be formed in natural (erosion of metallic minerals) and anthropogenic processes (energy production, metal processing and waste management) and polycyclic aromatic hydrocarbons (PAHs), which can be by-products of incomplete combustion processes of organic matter in the environment. Plants can easily sorb toxic elements and PAHs from contaminated environment through roots and tubers. As a result of FCM-food interactions, toxic elements and PAHs can migrate from FCM into food, which is an undesirable phenomenon as they exhibit mutagenic, genotoxic and carcinogenic effects on the health (Bansal & Kim, 2015; Joseph, Jun, Flora, Park & Yoon, 2019; Ghuniem, Khorshed, El-Safty, Souaya & Khalil, 2020; Sampaio et al., 2021). Faculty of Chemistry Adam Mickiewicz University in Poznań 42 Some PAHs may be degraded to carbonyl compounds in the environment (William, Pangzhen, Danyang & Zhongxiang, 2023). Carbonyl compounds (low molecular weight aldehydes and ketones) belong to the group of chemicals ubiquitous in the environment (Szeląg-Wasielewska & Dąbrowska 2020; Aznar, Domeño, Osorio & Nerin, 2020; Sauter et al., 2021; Werner, et al., 2024). Some of them are classified as by- products of polymerization process (Cincotta, Verzera, Tripodi & Condurso, 2018; Dehghani, Farhang & Zarei, 2018; Abe et al., 2021; Cardozo, Pereira dos Anjos, Campos da Rocha & de Andrade, 2021; Dhaka et al., 2022). The presence of low molecular weight carbonyl compounds in food is undesirable and requires constant monitoring. Some aldehydes are considered carcinogenic, mutagenic and allergenic, such as formaldehyde and acetaldehyde (WHO 2011). In addition, the identification of a mixture of carbonyl compounds (saturated C3-C10 aldehydes, ketones) in food may suggest undesirable changes in the sensory profile of food, because aldehydes and ketones with simple structure are characterized by low sensory thresholds. Migration of carbonyl compounds from the surfaces of FCMs to food may be the reason for noticeable changes in the smell and taste of food (Gonzalez, Domenek, Plessis & Ducruet, 2017; Dehghani et al., 2018; Marín-Morocho, Domenek & Salazar, 2021; McGorrin, 2019; Osorio, Aznar & Nerin, 2019; Miralles, Yusa, Sanchis & Coscolla, 2021; Aznar et al., 2020). In addition, some manufacturing additives (e.g., bisphenol-A (BPA), bishpenol-S (BPS), photoinitiators, phthalates) should be used in moderation because they can exhibit proestrogenic effects and are defined as endocrine disrupting compounds (EDCs) (Ma et al., 2019; Dong et al., 2022; Heindel et al., 2022; Sawadogo et al., 2023; Prueitt et al., 2023; Topdas, 2023; Tsochatzis et al., 2023; Zhu et al., 2024). Due to the undesirable properties of many IAS and NIAS, target approach is needed to determine the impact of FCM on food sensory profile and quality. I) Overall migration study of volatile, odor-active contaminants Undesirable interactions between FCMs and food can include change the sensory profile of food for two reasons: as a result of migration of odor-active compounds from FCMs into food or sorption of key food odor-active compounds by FCMs. To evaluate the effect of FCMs on the sensory profile of food, a three-stage experiment was conducted, which include: I) determination of odor-active compounds characteristic of FCMs, Faculty of Chemistry Adam Mickiewicz University in Poznań 43 II) determination of odor-active compounds in coffee or tea whose presence was caused by the FCMs- food interactions, III) sensory evaluation of coffee and tea brewed in different FCMs. In all of the above steps, glass was treated as a reference material. Firstly, gas chromatography-olfactometry (GC-O) analysis was carried out to identify the volatile aroma compounds characteristic of FCMs. GC-O is an analytical technique that combines gas chromatography with human sensory detection to identify and evaluate odor-active compounds in complex mixtures. In GC-O, trained panelists sniff the effluent directly from the capillary column to detect and describe odor-active compounds as they elute from the chromatograph. Solvent-assisted flavor evaporation (SAFE), described by Engel, Bahr and Schieberle (1999), has found widespread application in the identification of key aroma compounds from various matrices (Majcher, Olszak-Ossowska, Szudera-Kończal & Jeleń, 2020; Gąsior et al., 2021). Prior to SAFE extraction, samples (50 g) were extracted with methylene chloride (100 mL) for 24 h by shaking in the IKA KS 130 shaker (Fig. 10). After the volatiles were isolated, the extract was dried over anhydrous sodium sulfate and concentrated with a Kuderna Danish concentrator to about 500 μL. Fig. 10. Sample preparation for analysis of odor-active compounds characteristic of FCMs; steps included: (I) - extraction with dichloromethane, (II) - SAFE, (III/IV)- concentration, (V) - GC-O analysis Odor-active compounds were identified from SAFE extracts by GC−O on a HP 5890 chromatograph (Hewlett-Packard, Wilmington, DE, U.S.A.) using two capillary columns with different polarities: SPB 5 (30 m × 0.53 mm × 1.5 μm) and SUPELCOWAX 10 (30 m × 0.53 mm × 1 μm) (Supelco, Bellefonte, PA, U.S.A.). GC was equipped with a Y splitter dividing the effluent 1:1 between the olfactometry port with humidified air as a makeup gas and a flame ionization detector. The operating Faculty of Chemistry Adam Mickiewicz University in Poznań 44 conditions were as follows for the SPB-5 column: initial oven temperature of 40°C (1 min) raised at 6°C/min to 180°C and at 20°C/min to 280°C. Operating conditions for the SUPELCOWAX 10 column were as follows: initial oven temperature of 40°C (2 min), raised to 240°C at 6°C/min rate and held for 2 min isothermally. The flavor extract (2 μL) was injected into a GC column using splitless mode. Odor-active regions were detected by GC-effluent sniffing (GC−O) and three panelists determined the description of the volatiles. For all peaks and flavor notes, Kovats Index (KI) were calculated to compare results obtained by GC−MS to literature data. KI were calculated for each compound using a homologous series of C7−C24 n-alkanes at a concentration 1 mg/mL, which was injected under the same chromatographic conditions. The samples were also identified using GC/TOF-MS (Agilent 7890&7820) to confirmed results obtained. Secondly, it was examined how FCMs affect the sensory profile of coffee and tea. For this purpose, coffee (10 g) or tea (1 tea bag ≈ 2 g) was brewed (250 ml water) and introduced to different FCMs: glass, palm leaf, paper, wood and wheat bran (covered with a lid of the same material). The samples were left for 30 minutes and then presented to the panelists (Figs. 11 I and 11 II). Sensory analyses of the coffee and tea samples were evaluated by 8 panel members (6 females and 2 males). Odor descriptors were selected according to the Basic Flavor Descriptive Language from Givaudan Roure Flavor, Ltd. established in preliminary tests and characterized as grassy, coffee-like, bitter, roasted, musty, cereal-like, earthy, woody, cardboard, citrus and fatty and fruity on a scale of 1–5, where 1 means “none” and 5 means “very strong”. The sensory tests were carried out in a conditioned room. I II Fig. 11. Samples of (I) coffee and (II) tea prepared for sensory evaluation At the same time, volatile compounds were extracted from the coffee or tea samples using headspace solid microextraction (HS-SPME). SPME fiber (CAR/PDMS/ DVB; 2 cm) was pre-treated in an Faculty of Chemistry Adam Mickiewicz University in Poznań 45 injection port at 270°C for 30 min before analysis. Filtered black coffee or tea extracts (5 mL), were introduced into 20 ml SPME vials and 5 g salt was added. Extraction was carried out at 50°C for 40 min. The fiber compounds were desorbed in the injection port of the GCxGC-TOF/MS apparatus for 5 min (Pegasus 4D, LECO, St. Joseph, MI). The GC system was equipped with a DB-5 primary column (25 m × 0.2 mm × 0.33 µm, Agilent Technologies, Santa Clara, CA) and Supelcowax-10 (1.2 m × 0.1 mm × 0.1 µm, Supelco, Bellefonte, PA) as a secondary column. Injector temperature was set at 240°C and injection was performed in a splitless mode. Gas flow was set at 0.8 mL/min. The primary oven temperature was programmed as follows: 40°C (1 min), 6°C/min to 20°C (0 min), 25°C (1 min) to 235°C (5 min). Secondary oven: 65°C (1 min), 6°C /1 min to 225°C (0 min) 25°C 1 min to 260°C (5 min). The transfer line temperature was 260°C. The modulation time was 4 sec. Time-of-flight mass spectrometer was operating at a mass range of m/z 33-383 and detector voltage – 1700 V at 150 spectra/sec. The data were collected and processed using LECO ChromaTOF v.4.40. The total analysis time was about 34 min. Three replicates were performed for each material. Volatile compounds were identified based on the mass spectra using the NIST library and based on the retention index using Leibniz-LSB@TUM Odorant Database. Semi-quantitative analysis was performed using an internal standard naphthalene (D8) (15.6 mg/25 mL MeOH). II) Migration study of volatile markers - carbonyl compounds Carbonyl compounds belong to a group of chemical compounds ubiquitous in the surrounding environment, in which they undergo dynamic changes and are highly reactive. The use of suitably sensitive analytical tools that allow monitoring the concentration levels of low-molecular-weight carbonyl compounds makes it possible to observe the changes taking place and establish correlations, even at low concentrations (ng/L). This means that these compounds can be successfully used as environmental markers. The intensity of migration of carbonyl compounds (and other contaminants) from FCMs into food can be determined by various physicochemical factors, e.g., type of FCMs, type of food (i.e., pH value), contact time and temperature between FCMs and food. Therefore, migration studies of carbonyl compounds (as markers) from FCMs into various food simulants at different times (15 min, 30 min, 2h, 5 h and 10 h), temperatures (5°C, 20°C, 60°C and 70°C), pH value (2.75-6.00) were carried out. Additionally, heating the food with popularly 700 W microwave radiation may also be an important factor that can influence the intensity of migration processes. FCMs with distilled water and 3 % acetic acid were stored under refrigeration (4°C) for different times (12 h, 24 h, 192 h), after which the sample was heated in a microwave oven for different times (1-4 min). Faculty of Chemistry Adam Mickiewicz University in Poznań 46 Carbonyl compounds dissolve well in polar matrices, therefore the determination of these compounds in polar matrices is difficult. Their isolation requires special preparation of samples for testing. The qualitative and quantitative determination of migrating carbonyl compounds was carried out using the technique proposed by Sclimenti, Krasner, Glaze and Weinberg (1990). The technique is based on the use of pre-derivatization of the sample with the reagent O-(2,3,4,5,6- pentafluorobenzyl)hydroxylamine (PFBOA), which allows the transformation of carbonyl compounds into less polar and more volatile oximes (Table 5). For most aldehydes, two geometric isomers are formed: E- and Z-PFBOA, except for symmetrical carbonyls, such as formaldehyde. Table 5. Formulas of oximes formed by the reaction of carbonyl compounds with the PFBOA reagent, their molecular masses, molar volume and density Carbonyl compound Example of derivatization process product with PFBOA reagent Molecular mass of oxime (Da)* Molar volume (cm3/mol)* Density (g/cm3)* formaldehyde H F F F F F O N H 225 157.7 ± 7.0 1.42 ± 0.10 acetaldehyde F F F F F O N H 239 173.8 ± 7.0 1.37 ± 0.10 propanal F F F F F O N H 253 189.9 ± 7.0 1.33 ± 0.10 butanal F F F F F O N H 267 206.0 ± 7.0 1.29 ± 0.10 Faculty of Chemistry Adam Mickiewicz University in Poznań 47 pentanal F F F F F O N H 281 222.1 ± 7.0 1.26 ± 0.10 hexanal F F F F F O N H 295 238.2 ± 7.0 1.23 ± 0.10 heptanal F F F F F O N H 309 254.3 ± 7.0 1.21 ± 0.10 octanal F F F F F O N H 323 270.4 ± 7.0 1.19 ± 0.10 benzaldehyde F F F F F O N H 301 226.7 ± 7.0 1.32 ± 0.10 nonanal F F F F F O N H 337 286.5 ± 7.0 1.17 ± 0.10 decanal F F F F F O N H 351 302.5 ± 7.0 1.16 ± 0.10 Faculty of Chemistry Adam Mickiewicz University in Poznań 48 glyoxal H F FF F F O N H O 253 172.0 ± 7.0 1.47 ± 0.10 methylglyoxal F FF F F O N H O 267 187.2 ± 7.0 1.42 ± 0.10 acetone F F F F F O N 253 189.1 ± 7.0 1.33 ± 0.10 pentan-2-one F F F F F O N 281 221.3 ± 7.0 1.27 ± 0.10 hexan-2-one F F F F F O N 295 237.4 ± 7.0 1.24 ± 0.10 octan-3-one F F F F F O N 323 269.5 ± 7.0 1.19 ± 0.10 *based on the ChemSketch Programme Database Faculty of Chemistry Adam Mickiewicz University in Poznań 49 1 ml of 2 mg/mL PFBOA aqueous solution was added to 50 mL of food simulants and left at room temperature for 1 h. 50 μL of concentrated sulfuric acid was added to complete the derivatization reaction. The oximes were extracted by liquid-liquid extraction (LLE) with 1 mL of hexane for 1 min. Then the extract was purified with 2 mL of 0.1 M sulfuric acid solution. The hexane extracts were analyzed by gas chromatography using a Fisons Instruments 8000 equipped with 63 Ni electron capture detectors (GC-ECD). Injections of 0.5 μL of the extract were introduced via “on column” injector into chromatographic column. A Rtx-5MS (Restek) fused silica capillary column (30m × 0.25mm i.d. × 0.25µm film thickness) was employed for analysis and a Rtx-1301 (Restek) fused silica capillary column (30m × 0.32mm i.d. × 0.5µm film thickness) was used as a confirmation column. Injector temperature was set at 80°C. Gas flow was set at 80 kPa. Helium was used as carrier gas and nitrogen was used as make-up gas for the detector. The analysis were carried out in a temperature program starting at 80°C for 4 min, then increasing the temperature to 240°C with an increase of 7°C/min and then to 290°C with an increase of 20°C/min. DataApex, Clarity 6.2, Czech Republic software was used to collect and process chromatographic data. Chromatograms of aldehyde and ketone standards are presented in Fig. 12. I II Fig. 12. Carbonyl compound standards: (I) aldehydes: (1) formaldehyde; (2) acetaldehyde; (3) propanal; (4) butanal; (5) pentanal; (6) hexanal; (7) heptanal; (8) octanal; (9) benzaldehyde; (10) nonanal; (11) decanal; (12) glyoxal; (13) methylglyoxal and (II) ketones: (14) acetone; (15) 2-pentanone; (16) 2-hexanone; (17) 3-octanone [min.]Time 5 10 15 20 25 [mV] V o lt a g e 0 200 400 600 G:\Agata\AAChromatogramy2024\chromatogramy do Food Chemistry\AB-AV-WZORZEC-AL-85-n2-12-04-24 - Detector 1 [min.]Time 5 10 15 20 [mV] V o lt a g e 0 200 400 600 800 I:\Agata\Moi doktoranci\00Karolina Brończyk\AAA-pisanie pracy\Chromatogramy\AB-AV-KETONY-150-n1-11-04-24 - Detector 1 1 2 3 4 3 5 3 6 3 7 3 8 3 9 3 10 3 11 3 12 3 13 3 14 3 15 16 17 Faculty of Chemistry Adam Mickiewicz University in Poznań 50 Quantification for carbonyl compounds was performed using an external standard calibration curve. All standards were prepared gravimetrically in concentration ranges 1-30 µg/L. The linearity of the calibration curve was calculated as the correlation coefficient (R), the value of which is greater than 0.9996 for all analytes. Limit of detection (LOD) and quantification (LOQ) were determined for each analyte using “Regression Statistics”. The precision of the method was evaluated in terms of repeatability and expressed as relative standard deviation (RSD %). The RSD% was obtained by analyzing the samples in optimized conditions, using three replicates and three points of calibration curve for each analyte. The analytical parameters of all migrants analyzed are shown in Table 6. III) Migration study of high-molecular weight contaminants Polycyclic aromatic hydrocarbons were determined by the GC-FID technique (HP 5890II) with autosampler and flame ionization detector (FID). The injection volume was 1 µL, injector and detector temperature were set at 280°C. The chromatograph was equipped with Rtx 5-W/Integra Guard capillary column (30 m × 0.25 mm × 0.25 µm, Restek, USA). The analysis was performed using helium as carrier gas at a flow rate of 1.75 mL/min. The initial column temperature was 90°C (hold for 3 min) and then ramped at 10°C/min to 270°C. The total analysis time was 21 min. Bisphenols and benzophenone derivatives were determined by the HPLC-DAD technique (Agilent 1100 Series HPLC System with Diode Array Detector). The injection volume was 1 µL. The chromatograph was equipped with an Ultra AQ C18 column (5 µm, 250 mm × 4.6 mm; Restek, USA). A mixture of acetonitrile and water in a volume ratio of 70:30 was used as the mobile phase in the analysis of BPA and BPS and methanol (100 %) was used in the analysis of 2,4-DHBP, 2,2,4,4'-THBP and 2-H-4- MBP, respectively. The mobile phase flow rate in both analyzes was 1 mL/min in isocratic mode. The total analysis time was 3 min for bisphenols and 4 min for benzophenone derivatives, respectively. Spectra were collected at a wavelength of λ = 254 nm. Quantification for each migrant was performed using an external standard calibration curve. All standards were prepared gravimetrically in concentration ranges: for ANT and PHE, 1-10 µg/L; and for BPA, BPS and benzophenone derivatives, 0.05-10.00 µg/L, respectively. All chromatographic data were obtained analogously to the carbonyl compounds and are presented in Table 6. Faculty of Chemistry Adam Mickiewicz University in Poznań 51 Table 6. List of tested organic contaminants with IAS/NIAS division and SML values (based on the Commission Regulations No. 10/2011 and No. 2018/213) and chromatographic data: retention time (min), standard curve equation (includes measurement errors of parameters a and b and expressed in the form y=a(±SE)x+b(±SE)), limit of detection (LOD), limit of quantification (LOQ) and relative standard deviation (RSD) Analytical tools Migrants IAS/NIAS SML Retention time (min) Calibration curve LOD (μg/l) LOQ (μg/l) RSD (%) GC-ECD formaldehyde IAS 15 5.68 y=41(±2)x + 291(±24) 0.003 0.009 9.8 acetaldehyde IAS 6 8.10; 8.24 y=82(±3)x + 457(±42) 0.005 0.015 9.1 acetone NIAS - 8,56 y=184(±10)x + 1217(±158) 0.020 0.060 6.5 propanal NIAS - 8.94; 9.07 y=37(±2)x + 502(±65) 0.015 0.045 9.8 butanal NIAS - 10.65; 10.76 y=51(±3)x + 893(±25) 0.020 0.060 9.9 pentan-2-one NIAS - 11.25; 11.40 y=8(±1)x + 905(±166) 0.012 0.040 6.4 pentanal NIAS - 12.44; 12.54 y=57(±3)x + 906(±30) 0.020 0.080 9.9 hexan-2-one NIAS - 12.84; 13.05 y=7(±1)x + 787(±31) 0.020 0.080 6.4 octan-3-one NIAS - 14.51; 14.76 y=5(±1) + 534(±49) 0.060 0.190 5.2 hexanal NIAS - 15.15; 15.25 y=210(±4)x+622(±35) 0.003 0.009 6.4 heptanal NIAS - 16.95; 17.00 y=41(±1)x + 148(±4) 0.003 0.009 6.8 octanal NIAS - 17.76 y=72(±3)x + 215(±28) 0.010 0.030 9.9 benzaldehyde NIAS - 20.12 y=38(±2)x - 60(±8) 0.010 0.030 8.8 nonanal NIAS - 20.38 y=26(±1)x + 122(±9) 0.010 0.030 8.7 decanal NIAS - 21.00 y=15(±1)x + 148(±6) 0.020 0.090 9.9 Faculty of Chemistry Adam Mickiewicz University in Poznań 52 glyoxal NIAS - 23.23; 23.50 y=48(±2)x + 851(±28) 0.015 0.045 6.8 methylglyoxal NIAS - 23.84 y=22(±1)x +795(±9) 0.015 0.045 7.5 GC-FID phenanthrene (PHE) NIAS - 14.67 y=2.70(±0.15)x-1.60(±0.69) 0.88 2.70 8.5 anthracene (ANT) NIAS - 14.79 y = 1.51(±0.07)x -0.91(±0.34) 0.77 2.30 9.3 HPLC-DAD bisphenol-A (BPA) IAS 0.05 2.89 y=1.07(±0.02)x + 4.05(±0.57) 0.12 0.36 1.8 bisphenol-S (BPS) IAS 0.05 2.33 y=1.27(±0.09)x + 2.49(±0.04) 0.13 0.38 1.7 2,4- dihydroxybenzophenone (2,4-DHBP) IAS 6* 3.19 y=3.55(±0.05)x + 0.14(±0.10) 0.13 0.38 2.3 2,2’,4,4’- tetrahydroxybenzophenone (2,2’,4,4’-THBP) NIAS - 2.80 y=1.84(±0.11)x + 0.09(±0.02) 0.52 1.60 9.7 2-hydroxy-4- metoxybenzophenone (2-H-4-MBP) IAS 6* 3.74 y=4.02(±0.16)x + 0.33(±0.03) 0.35 1.10 5.9 * expressed as total specific migration limit (SML(T)) for 2,4-DHBP and 2-H-4-MBP Faculty of Chemistry Adam Mickiewicz University in Poznań 53 Tenax (food simulant E) is a porous organic polymer that has high chemical stability (up to 350°C) (Alfeeli, Taylor & Agah, 2010). However, some studies report disadvantages of Tenax as a food simulant, including the cost of the reagent, the need for long-term regeneration and the difficult management of Tenax due to static electricity from friction (Rubio et al., 2019). The use of Tenax can also lead to inflated IAS and NIAS concentrations compared to actual food samples (Rubio et al., 2019; Baele, Vermeulen, Claes, Ragaert & De Meulenaer, 2020). These reports suggest that interpretation of the results of Tenax migration studies should be cautious. Therefore, it is important to compare the intensity of FCMs-Tenax and FCMs-real food interactions to better understand the factors affecting the migration processes that occur. The Brunauer-Emmett-Teller (BET) gas adsorption method has become the most widely used standard procedure for determining the surface area of fine-grained and porous materials from adsorption data. This method is based on the physical adsorption of a vapour or gas into the surface of a solid. The specific surface area and pore size (BET isotherm) of Tenax and food samples (powdered milk, baby cereal, oat flakes) were examined, to evaluate the influence of the structure of simulated and real foods and the properties of contaminants on the intensity of migration processes. The composition of the food analyzed is summarized in Table 7. Table 7. Description of the composition of the food samples (expressed in g/100g of product), according to the manufacturer's data Food sample Content of Fat (including saturated fatty acids) Carbohydrates (including sugars) Fiber Protein Salt Mineral components Granulated, non-fat powdered milk 0.80 51.00 NS* 35.00 1.20 Calcium (1.404) Phosphorus (1.012) Baby cereal 1.40 87.00 2.10 7.60 0.02 Sodium (6.5) Whole grain oat flakes 6.90 60.00 9.80 12.00 <0.01 NS* NS*: not specified by the manufacturer Faculty of Chemistry Adam Mickiewicz University in Poznań 54 High-purity nitrogen (> 99.999 %) was used as adsorbate. The powdered materials were pre- gassed at 100°C for 24 hours. The selection of pre-degassing parameters took into account resistance to elevated temperatures, including susceptibility to changes in pore structure. The sample was then filled with nitrogen and weighed to determine the real (dry) weight of the sample. The pre-gassed sample vial and the weighing vial (empty) were sealed in an Autosorb iQ Station 1 port transducer, Quantachrome® ASiQwin™ Automatic Gas Sorption Data Acquisition and Reduction ©1994-2013, Quantachrome Instruments version 3.01. and then immersed in liquid nitrogen at 77.35 K. Measurement of gas adsorption on the test material consisted of gradually filling the volume of two vials with the same amount of nitrogen in the relative pressure range from 0.01 to 0.99 p/p0. In the next experiment, the adsorption capacity of Tenax and food samples (powdered milk; infant cereal and oatmeal) and the influence of the physical properties of migrant compounds on the intensity of migration processes were evaluated, as recovery test. The spiking experiment was conducted as follows: 1 mL of standard solutions of the tested migrating compounds (2,4-DHBP, 2,2',4,4'-THBP; 2-H-4-MBP; PHE and ANT) containing analytes at appropriate concentrations were applied to a glass Petri dish to obtain a final concentration of 3 µg/L for 2,4-DHBP, 2,2',4,4'-THBP and 2- H-4-MBP and 5 µg/L for ANT and PHE. These chemical compounds were chosen because of their similar structure, but different molecular weights. One g of Tenax or food (powdered milk; baby cereal and oat flakes) was applied to the materials, then wrapped in aluminum foil and placed in an oven heated to 70°C for 2 hours. Samples were then prepared according to migration tests typical of Tenax, i.e., double extraction with 25 mL of solvent (acetone, methanol) within 1 h at ambient temperature and concentration by vacuum evaporation (p = 850 hPa). The amount of adsorbed contaminants was determined by appropriate chromatographic techniques (GC-FID and HPLC-DAD). IV) Migration study of inorganic contaminants Inorganic contaminants pose a particular challenge in food safety control, due to the harmfulness of many elements even at low (trace) concentration levels. In order to assess the risk of migration of various elements, the total content of elements in FCMs and in food simulants after their contact with FCMs (after 30 min and 10h at 60°C) was determined. The steps of the analytical procedure consisted of: Faculty of Chemistry Adam Mickiewicz University in Poznań 55 I) determination of the analytical problem and selection of the appropriate analytical technique, II) development of sample preparation for ICP-MS analysis, III) optimization of ICP-MS - calibration, interference correction, IV) validation of the analytical procedure - determination of validation parameters, V) performance of analyses and verification of the analytical method, VI) statistical processing of the results and their interpretation. The sample preparation step is crucial in the analysis. It should be characterized by the highest possible efficiency and reproducibility. Two sample preparation methods were used: mineralization and extraction, in order to evaluate the elemental composition of analyzed FCMs. Pre-preparation of FCMs samples for mineralization consisted of gentle washing with demineralized water (cleaning the surface of the raw material from dust) and drying at 40 oC in a laboratory dryer. Digestion of the powdered samples of FCMs (homogenous samples) were carried out in the EthosOne (Millestone, Italy) closed microwave mineralization system in the next step. For this purpose, 0.5000±0.0001 g of FCM samples were placed in a Teflon vessel with 8 mL of concentrated (65 %) HNO3 (analytical purity, Merck, Darmstadt, Germany) and 1 mL of H2O2 (Merck, Darmstadt, Germany). The program of digestion included the following stages: I) first stage - temperature to 80°C, 10 min, power 600 W; II) second stage - temperature 140°C, 12 min, power 1200 W; III) third stage - temperature 180°C, 15 min, power 1200 W. The solutions were and made up to a final volume of 15 mL with deionized water. Extraction experiment was conducted in the second step. Elements were determined in food simulants: neutral (distilled water) and acidic (3 % acetic acid) after migration studies with FCMs, which were conducted in different conditions: 30 min (short contact) and 10 h (long contact) at 60°C (in accordance with Regulation (EU) No 10/2011). Based on two experiments, the percentage of migration of various elements