A Comprehensive Review on Microplastic Contamination in Food Packaging and Processing: Pathways, Exposure, and Implications

Due to widespread environmental presence and growing detection in food systems, microplastics (MPs), which are plastic particles smaller than 5 mm, along with nanoplastics with size <1 µm, collectively referred to as micro and nanoplastics (MNPs), have become a growing global concern. Previous exposure studies undermined the true burden of plastic contamination, owing to the limited analytical detection range that resulted in the omission of nanoscale fractions and a potential underestimation of related toxicological risks. Recent studies have reported that approximately 90% of plastic particles detected in bottled water are MNPs. Food packaging materials are a crucial but frequently disregarded source of MP contamination among the various exposure pathways. During handling, processing, and storage, packaging plastics can release MPs into food, which has a direct impact on consumer health and food safety. Measurable concentrations of MPs with variable contamination profiles have been found in packaged beverages, dairy products, meat, snacks, and ready-to-eat foods, as per recent case studies. Despite ongoing methodological issues with size resolution, polymer discrimination, and sample standardization, various analytical techniques have been used for detection and characterization of MPs. The necessity of reducing MPs' presence in food systems is highlighted by their toxicological effects, which include possible bioaccumulation, oxidative stress, endocrine disruption, and microbiota imbalance. Reducing exposure risks requires the implementation of preventive measures like better manufacturing techniques, sustainable packaging substitutes, and regulatory actions. The sources, migration, analytical techniques, health effects, and preventative measures of MPs in food packaging are summarized in this review. It also highlights research gaps and obstacles in developing sustainable and safe food packaging.