Safety of Plastic Food Packaging: The Challenges about Non-Intentionally Added Substances (NIAS) Discovery, Identification and Risk Assessment

Abstract

Several food contact materials (FCMs) contain non-intentionally added substances (NIAS), and most of the substances that migrate from plastic food packaging are unknown. This review aimed to situate the main challenges involving unknown NIAS in plastic food packaging in terms of identification, migration tests, prediction, sample preparation, determination methods and risk assessment trials. Most studies have identified NIAS in plastic materials as polyurethane adhesives (PU), polyethylene terephthalate (PET), polyester coatings, polypropylene materials (PP), multilayers materials, plastic films, polyvinyl chloride (PVC), recycled materials, high-density polyethylene (HDPE) and low-density polyethylene (LDPE). Degradation products are almost the primary source of NIAS in plastic FCMs, most from antioxidants as Irganox 1010 and Irgafos 168, following by oligomers and side reaction products. The NIAS assessment in plastics FCMs is usually made by migration tests under worst-case conditions using food simulants. For predicted NIAS, targeted analytical methods are applied using GC-MS based methods for volatile NIAS and GC-MS and LC-MS based methods for semi- and non-volatile NIAS; non-targeted methods to analyze unknown NIAS in plastic FCMs are applied using GC and LC techniques combined with QTOF mass spectrometry (HRMS). In terms of NIAS risk assessment and prioritization, the threshold of toxicological concern (TTC) concept is the most applied tool for risk assessment. Bioassays with sensitive analytical techniques seem to be an efficient method to identify NIAS and their hazard to human exposure; the combination of genotoxicity testing with analytical chemistry could allow the Cramer class III TTC application to prioritize unknown NIAS. The scientific justification for implementing a molecular weight-based cut-off (<1000 Da) in the risk assessment of FCMs should be reevaluated. Although official guides and opinions are being issued on the subject, the whole chain’s alignment is needed, and more specific legislation on the steps to follow to get along with NIAS.

Natural Deep Eutectic Solvent-Based Dispersive Liquid–Liquid Microextraction Coupled with Direct Analysis in Real Time Mass Spectrometry: A Green Temperature-Mediated Analytical Strategy

“…Food may be in contact with FCMs ( e.g., plastics) during production, storage, transportation, and serving before eventual consumption. To ensure the safety of FCMs, there should be no migrations of chemical substances from FCMs to food at the levels posing harm to human health. , Phthalate esters, a class of common plasticizers with restricted use in plastic FCMs due to adverse health effects, were selected as model compounds for method development and validation. The selection of a suitable combination of extraction method and solvent is of critical importance.…”

Towards Higher Quality of Recycled Plastics: Limitations from the Material’s Perspective

“…Next to the issues arising from the combination of different polymeric and non-polymeric materials, major limitations in the polymers' recyclability result to be inherent to the material, owing to its structural composition. In this sense, additives have proven to be a source of contamination generating organic substances, the behaviour of which is still under investigation [116,117]. The presence of these substances per se does not represent a recyclability burden.…”

Food and beverage can coatings: A review on chemical analysis, migration, and risk assessment

“…In addition to intentionally added substances, such as prepolymers, monomers, additives, catalysts, and so on, the final material may also contain the so‐called nonintentionally added substances (NIAS), such as impurities, reaction products, degradation products, and so on. Thus, a large number of substances can be present in the final materials and have the potential to migrate into the foodstuffs (Aznar et al., 2015; Kato & Conte‐Junior, 2021; Nerín et al, 2022). Migration is a mass transfer phenomenon where the substance transferred from the packaging to the food is called migrant.…”