Migration of substances from food contact plastic materials into foodstuff and their implications for human exposure

Migration of Chemical Compounds from Packaging Materials into Packaged Foods: Interaction, Mechanism, Assessment, and Regulations

The migration of chemical compounds from packaging polymers to food presents a multifaceted challenge with implications for food safety and public health. This review explores the interaction between packaging materials and food products, focusing on permeation, migration, and sorption processes. The different migration mechanisms of contact migration, gas phase migration, penetration migration, set-off migration, and condensation/distillation migration have been discussed comprehensively. The major migrating compounds are plasticizers, nanoparticles, antioxidants, light stabilizers, thermal stabilizers, monomers, oligomers, printing inks, and adhesives, posing potential health risks due to their association with endocrine disruption and carcinogenic effects. Advanced analytical methods help in the monitoring of migrated compounds, facilitating compliance with regulatory standards. Regulatory agencies enforce guidelines to limit migration, prompting the development of barrier coatings and safer packaging alternatives. Furthermore, there is a need to decipher the migration mechanism for mitigating it along with advancements in analytical techniques for monitoring the migration of compounds.

A study on the performance, structure, composition, and release behavior changes of polybutylene adipate terephthalic acid (PBAT) film during food contact

Polybutylene adipate terephthalic acid (PBAT) is an emerging biodegradable material in food packaging. However, concerns have been raised regarding the potential hazards it could pose to food safety. In this study, the changes of PBAT films during food contact and the release of small molecules were inestigated by a multiscale approach. On a macro-scale, the surface roughness of the films increased with the reduction in the concentration of food simulants and the increase in contact temperatures, especially after immersion in acidic food environments. On a micro-scale, the crystallinity (Xc) and degradation indexes (DI) of the films increased by 5.7-61.2% and 7.8-48.6%, respectively, which led to a decrease in thermal stability. On a scale approaching the molecular level, 2,4-di-tert-butylphenol (2,4-DTBP) was detected by gas chromatography-mass spectrometry (GC-MS/MS) with the highest migration content, and the release behavior of 2,4-DTBP was further investigated by migration kinetics. In addition, terephthalic acid (TPA), a hydrolysis product of PBAT, was detected in acidic food environments by liquid chromatography-mass spectrometry (LC-MS/MS). The results of this study could provide practical guidance and assistance to promote sustainable development in the field of food packaging.

Self-Formation of Lignin Particles Through Melt-Extrusion for Active Biodegradable Food Packaging

This study presents a method for the self-formation of lignin particles within a polylactic acid (PLA) matrix during melt-extrusion, eliminating the need for separation and drying steps typically associated with submicro-size lignin particles. This method effectively mitigates the problem of agglomeration often associated with the drying step. Softwood kraft lignin, guaiacyl lignin (GL-lignin), was dissolved in low-molecular-weight poly(ethylene glycol) (PEG) and was introduced into a twin-screw extruder using a liquid feeder. Lignin particles within a particle size range of 200-500 nm were observed in the extrudate of the PLA/PEG/GL-lignin composites. PLA/PEG/GL-lignin composite films were produced through blown film extrusion. These composite films demonstrated superior ultraviolet (UV)-barrier and antioxidant properties compared to neat PLA films, with optical and mechanical characteristics comparable to those of neat PLA. Moreover, migration values of the composite films in various food simulants were below regulatory limits, suggesting their potential for food packaging applications. This self-formation process offers a promising approach for utilizing lignin for PLA applications.

Recovery of an Antioxidant Derived from a Phenolic Diphosphite from Wastewater during the Production of a Polypropylene Compound: A Step towards Sustainable Management

Organic phosphoester (OPE) antioxidants are currently required due to their contribution to enhancing the quality of polymers, including polypropylene (PP). In this research, an integral methodology is presented for the efficient extraction of bis(2,4-dicumylphenyl) pentaerythritol diphosphite from industrial wastewater. Upon employing the solid-phase extraction (SPE) technique, the recovered compound is subjected to a comprehensive analysis of the recovered compound using high-performance liquid chromatography (HPLC), mass spectrometry (MS), thermal analysis (TGA), Fourier transforms infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). Subsequently, purified Bis(2,4-dicumylphenyl) pentaerythritol diphosphite was evaluated as a thermo-oxidative stabilizer after incorporation into PP resins. The relative standard deviation (RSD), Error (Er), linearity (R2), and percentage (%) recovery were less than 2.6, 2.5, more significant than 0.9995, and greater than 96%, respectively, for the inter-day and intra-day tests of the chromatographic method and the SPE. Except for chloroform, which was necessary due to the solubility properties of the investigated analyte, the use of environmentally friendly solvents, such as methanol and acetonitrile, was considered during the development of this research. The OPE extracted from industrial wastewater was characterized by FTIR, UV-Vis, DSC, TGA, and MS, allowing the elucidation of the structure of Bis(2,4-dicumylphenyl) pentaerythritol diphosphite (BDPD). The recovered OPE was mixed with PP resins, allowing it to improve its thermal properties and minimize its thermo-oxidative degradation. Organophosphorus flame retardant (OPE)' concentration in wastewater is alarming, ranging from 1179.0 to 4709.6 mg L-1. These exceed toxicity thresholds for aquatic organisms, emphasizing global environmental risks. Using a validated solid-phase extraction (SPE) technique with over 94% recovery, the study addresses concerns by removing organic contaminants and supporting circular economy principles. The high economic and environmental significance of recovering BDPD underscores the need for urgent global attention and intervention.

Assessment of heavy metals migrated from food contact plastic packaging: Bangladesh perspective

Plastic-based food-contact materials are potentially threatening the environment and public health by releasing toxic heavy metals. This study aimed to identify the types of plastic commonly used in Bangladesh as food-contact materials (FCMs) and assess the migration of heavy metals from these FCMs. Plastic types were identified using attenuated total reflectance fourier transform infrared spectroscopy (ATR-FTIR), and 25 samples were selected based on the category, including Polyethylene Terephthalate (PET), Polyethylene (PE), Polypropylene (PP), Polystyrene (PS), and Polycarbonate (PC). Distilled water, 3% acetic acid, and 15% ethanol were used as food simulants to assess the overall migration of chemicals at 70 °C for 2 h. The concentrations of heavy metals (Pb, Cd, Hg, Cr, and Sb) were analyzed using an Atomic Absorption Spectrophotometer (AAS). Results revealed that the highest overall migration occurred in coffee cups measuring 3.50 ± 0.17 mg/kg (using water simulant) and in yogurt containers with a measurement of 9.17 ± 0.1 mg/kg (using 3% acetic acid). The highest concentrations of Pb, Cd, Hg, Cr, and Sb were found in PP-2 (0.45 ± 0.01 mg/kg), PP-2 (0.36 ± 0.01 mg/kg), PC-5 (0.27 ± 0.01 mg/kg), PET-2 (0.12 ± 0.01 mg/kg), and PET-1 (0.09 ± 0.01 mg/kg), respectively. The concentration of heavy metals migrated from the containers is likely to induce a health risk due to bioaccumulation from long-term ingestion of food packaged in them. The findings of this study added knowledge about harmful heavy metals leached from the FCMs in Bangladesh.

Simultaneous Determination and Exposure Assessment of Antioxidants in Food Contact Plastic Materials by HPLC-MS/MS

Antioxidants are widely used to prevent oxidative degradation of food-contact plastics materials. However, when plastic products come into contact with food, antioxidants may contaminate food. Herein, twenty-three kinds of possible antioxidants were monitored in 257 products of seven polymers. The migration of antioxidants into the food simulants at different temperatures and times was detected by using HPLC-MS/MS. Risk assessment was performed based on the EU, U.S. FDA methods and Monte Carlo simulation. The antioxidants migrated mainly to fatty food simulant, with the highest concentration and occurrence frequency of Irgafos 168, followed byIrganox 1010, Irganox 1076, and Antioxidant LTDP in polyethylene terephthalate, polyvinyl chloride, polypropylene, polyethylene. No antioxidants were detected in polystyrene, polycarbonate, and polyvinylidene chloride. Additionally, antioxidants exhibited the highest detection rate of 0.81 in polyethylene. Risk assessment demonstrated that the antioxidants have no obvious health risk to the exposed population. However, the risk of polypropylene was relatively high compared to other polymers.

Consumers' practices and safety perceptions regarding the use of materials for food preparation and storage: Analyses by age group

Food Contact Materials (FCM) are those intended to be in contact with food, during its production, handling, and storage. FCM contain chemicals that could migrate to the foodstuff, posing potential health concerns, and usage practices influence the level of migration. This study assesses the preferences, safety perceptions, and usage practices of Portuguese consumers regarding FCM used for cooking and food storage (cookware). An observational, quantitative, and transversal study was performed through an online survey created for this purpose, which involved 1179 Portuguese adults. Results were analyzed according to age. Safety was the factor considered most important when choosing cookware materials, although the choice criteria varied with age. The majority of respondents recognize the risk of food contamination through cookware. Stainless steel and glass were considered the safest materials for cooking. The materials most used to reserve food are glass and plastic. Older individuals carry out more maintenance of cookware and have greater knowledge about how to wash and store it. Regarding the FCM symbology, there is a general lack of knowledge. Our study demonstrates the need to disseminate reliable information to the general public about cookware, contributing to greater literacy in health and to less exposure to food contact chemicals.

Occurrence of meso/micro/nano plastics and plastic additives in food from food packaging

This chapter focuses on the occurrence of plastic constituents in food due to the contact with different types of plastic packaging, films and coatings. The type of mechanisms occurring during the contamination of food by different packaging materials are described, as well as how the type of food and packaging may influences the extent of contamination. The main types of contaminants phenomena are considered and comprehensively discussed, along with the regulations in force for the use of plastic food packaging. In addition, the types of migration phenomena and factors that may influence such migration are comprehensively highlighted. Moreover, migration components related to the packaging polymers (monomers and oligomers) and the packaging additives are individually discussed in terms of chemical structure, adverse effects on foodstuffs, health, migration factors, as well as regulated residual values of such components.

Development of quantitative structure-retention relationship models to improve the identification of leachables in food packaging using non-targeted analysis

Quantitative structure-retention relationship (QSRR) models can be used to predict the chromatographic retention time of chemicals and facilitate the identification of unknown compounds, notably with non-targeted analysis. In this study, QSRR models were developed from the data obtained for 178 pure chemical standards and four types of analytical columns (C18, phenylhexyl, pentafluorophenyl, cyano) in liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS). First, different data partitioning ratios and feature selection methods [random forest (RF) and support vector machine (SVM)] were tested to build models to predict chromatographic retention times based on 2D molecular descriptors. The internal and external performances of the non-linear (RF) and corresponding linear predictive models were systematically compared, and RF models resulted in better predictive capacities [p < 0.05, with an average PVE (proportion of variance explained) value of 0.89 ± 0.02] than linear models (0.79 ± 0.03). For each column, the resulting model was applied to identify leachables from actual plastic packaging samples. An in-depth investigation of the top 20 most intense molecular features revealed that all false-positives could be identified as outliers in the QSRR models (outside of the 95% prediction bands). Furthermore, analyzing a sample on multiple chromatographic columns and applying the associated QSRR models increased the capacity to filter false positives. Such an approach will contribute to a more effective identification of unknown or unexpected leachables in plastics (e.g. non-intended added substances), therefore refining our understanding of the chemical risks associated with food contact materials.

Assessing Chemical Migration from Plastic Food Packaging into Food Simulant by Gas and Liquid Chromatography with High-Resolution Mass Spectrometry

Some components of plastic food packaging can migrate into food, and whereas migration studies of known components are required and relatively straightforward, identification of nonintentionally added substances (NIAS; unknowns) is challenging yet imperative to better characterizing food safety. To this aim, migration was investigated across 24 unique plastic food packaging products including plastic wrap, storage bags, vacuum bags, and meat trays. Gas and liquid chromatography separation systems coupled with Orbitrap mass analyzers were used for comprehensive nontargeted screening of migrants. Tentative identifications of features were assigned by searching commercial databases (e.g., NIST, MZCloud, ChemSpider, Extractables and Leachables) and filtering results based on mass accuracy, retention time indices, and mass spectral patterns. Several migrants showed elevated levels in specific food packaging types, particularly meat trays and plastic wrap, and varying degrees of migration over the 10 days. Eleven putative migrants are listed as substances of potential concern or priority hazardous substances. Additionally, migration amounts of an Irgafos 168 degradation product determined by semiquantitation exceeded proposed theoretical maximum migration values.