Toxicological Risk Assessment of Zinc Oxide and Silver Nanoparticles in Food Packaging

The integration of nanotechnology into the food packaging sector has generated a paradigm shift in food preservation, offering superior antimicrobial and barrier properties. However, the transition from conventional materials to nanocomposites raises fundamental questions regarding “nano-safety” and the potential impact on human health. This review paper critically analyzes current scientific literature on the toxicological risk associated with metallic nanoparticles, with a particular focus on zinc oxide (ZnO NPs) and silver (AgNPs). The complex mechanisms through which these submicroscopic entities can interact with biological systems—from inhalation and dermal contact to ingestion through the gastrointestinal tract—are explored. The analysis focuses on the importance of rigorous physicochemical characterization—including morphology, surface charge, and adsorption capacity—as a mandatory prerequisite in toxicity assessment. Furthermore, the paper examines current testing methodologies, drawing a parallel between the efficiency of in vitro models (oxidative stress, apoptosis, genotoxicity) and the complexity of in vivo studies (biodistribution, clearance, histopathology). A significant segment is dedicated to the dynamics of migration from the polymer matrix into food, evaluating influencing factors such as pH, temperature, and contact time. Finally, directives and guidelines issued by the European Food Safety Authority (EFSA) and REACH regulations are reviewed, providing a theoretical perspective on how scientific and political consensus attempts to define safety limits for the modern consumer.