Migration testing of microplastics in plastic food-contact materials: Release, characterization, pollution level, and influencing factors

Thermal stresses during storage and usage impact plastic food-contact materials, causing microplastic migration into food. The research on this topic has recently garnered significant attention, and a thorough understanding of the efforts undertaken to advance this field is vital but lacking. This systematic review of 35 peer-reviewed publications aims to close this gap by assessing current migration testing and characterization approaches, as well as contamination prevention measures, keeping abreast of recent advancements, and presenting key considerations and recommendations for future research. Overall, microplastic migration is studied by subjecting food-simulating liquids to conventional and microwave heating and storage conditions, often utilizing electron microscopic imaging or spectroscopy. Teabags and single-use disposable cups are the most studied and have a higher likelihood of microplastic migration. The dearth of method standardization makes comparing studies difficult and merits attention. More research is needed to understand the potential risks to human health from their exposure.