## 4 Sample Preparation
### Migration Tests Using Food Simulants  
Migration testing under controlled laboratory conditions remains the most common practice for evaluating the release of substances from plastic FCMs into food, as established by Regulation (EU) 10/2011 [7] and its recent amendment [8]. This regulation defines standardized food simulants (e.g., aqueous, acidic, alcoholic, or fatty substitutes) and testing conditions (time and temperature) tailored to the intended use of the material. Among the 54 reviewed studies in Table 1, migration tests were widely employed to simulate both routine and extreme scenarios, such as long-term storage, microwave heating, or dishwashing. A summary of the most common food simulants and their applications in the reviewed studies is depicted in Figure 1. However, despite their regulatory value, food simulants may not fully replicate real food matrices and can sometimes lead to the over- or underestimation of actual migration, particularly for hydrophobic or reactive compounds. For aqueous and acidic foods (simulants A: 10% ethanol (EtOH), B: 3% acetic acid, and C: 20% EtOH, all in water solution), studies often applied conditions of 40-60 \({}^{\circ}\)C for 10 days to mimic long-term storage [20; 63]. For instance, [PERSON] et al. [25] tested PP microwavedale containers with simulant A at 40 \({}^{\circ}\)C for 10 days to reflect typical reheating practices. In the study conducted by [PERSON] et al. [66], ethylene-vinyl acetate (EVA) corks, intended to be used as sealants for wine bottles, were exposed to simulants B and C at 60 \({}^{\circ}\)C for 10 days. Fatty food simulants (D1: 50% EtOH in water; D2: vegetable oil and its substitutes and 95% EtOH or isooctane) are also frequently used. For example, [PERSON] et al. [50] performed migration testing of multilayer PE films, including rLDPE, with simulant D2 (95% EtOH) at 20, 40, and 60 \({}^{\circ}\)C for 10 days to evaluate the migration of different chemical compounds, such as antioxidants and oligomers, from food packaging into fatty foods. High-temperature migration testing was applied to PA kitchenware, such as soup spoons, using food simulant D2 (95% EtOH) at 70 \({}^{\circ}\)C for 2 h to simulate cooking and use conditions [33]. Similarly, styrene-acrylonitrile copolymer (SAN) and acrylonitrile-butadiene-styrene (ABS) kitchenware were tested at 70-100 \({}^{\circ}\)C for 2 h using different simulants in the work conducted by [PERSON] et al. [37]. Regulation (EU) 10/2011 also outlines specific protocols for repeated-use articles [7]. For example, baby feeding bottles have been tested with food simulant D1 at 70 \({}^{\circ}\)C for 2 h to simulate repeated sterilization cycles and NIAS migration into hot milk [26; 43]. Similarly, reusable plastic bottles made from PE, polycarbonate (PC), and other polymers were tested  
Figure 1: Common food simulants and their applications for migration testing of plastic FCMs. with water at room temperature for 24-48 h to model daily use, revealing the migration of oligomers and slip agents even after dishwashing [57; 58]. Microwave and oven exposure, though not explicitly detailed in Regulation (EU) 10/2011, were incorporated into migration protocols to address real heating scenarios. For instance, microwave trays and oven bags were tested at 700 W for 5 min (max 102 \({}^{\circ}\)C) using simulant D2 (95% EtOH), showing higher migration levels of photoinitiators and plasticizers compared to conventional oven heating [52]. Migration into dry foods, using food simulant E (Tenax(), Verona, Italy), was tested on polyolefin films and multilayer packaging. For example, Tenax migration at 60 \({}^{\circ}\)C for 10 days effectively captured volatile NIAS like aldehydes and hydrocarbons from PP and PE films [65]. Similarly, in the work conducted by [PERSON] et al. [29], migration from several plastic films composed of PE, PET, PA, PP, and EVA was tested using simulant E at 60 \({}^{\circ}\)C for 10 days to identify potential migrants in packaging.