Micro- and nanoplastics in food contact materials: a comprehensive synthesis of release mechanisms, analytical evidence, and risk implications

Micro- and nanoplastics (MNPs) have emerged as a critical group of contaminants in food systems, particularly due to their release from food contact materials (FCMs). In 2025, the European Food Safety Authority (EFSA) published an extensive literature review analysing the mechanisms, extent, and implications of MNP release from common packaging polymers. Polymers such as polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polystyrene (PS), and polylactic acid (PLA) can emit micro- and nanosized particles during production, handling, heating, or storage. Physicochemical degradation processes, including thermo-oxidation, photo-oxidation, hydrolysis, and mechanical abrasion, mainly drive the release. Analytical studies have identified significant variability in particle detection using methods such as Fourier-transform infrared (FTIR) and Raman microspectroscopy, pyrolysis–gas chromatography/mass spectrometry (Py-GC/MS), and laser direct infrared (LDIR) imaging. Reported concentrations typically range from 10² to 10⁶ particles per litre, depending on polymer type, exposure time, and temperature. Despite technological progress, a lack of harmonised protocols, certified reference materials, and unified reporting metrics continues to limit comparability among studies. Although the toxicological significance of MNP exposure from packaging is not yet fully understood, cumulative intake through packaging, environmental, and dietary sources remains an emerging concern. EFSA emphasised the urgent need for method harmonisation, development of reference materials, and comprehensive risk assessment integrating analytical, exposure, and toxicological data.