Microplastics as unexplored emerging contaminant: A challenge for food safety

Microplastics (MPs) have emerged as a pervasive environmental contaminant with growing relevance to the food chain and human health. Defined as plastic particles smaller than 5 mm, MPs originate from the degradation of larger plastic debris or are directly released as primary microplastics from industrial and consumer products. These particles are now widely detected in terrestrial, freshwater, and marine ecosystems, enabling their entry into the food chain through ingestion by a wide range of organisms. Evidence shows that MPs accumulate in lower trophic levels, such as plankton and invertebrates, and are subsequently transferred to higher trophic organisms, including fish, livestock, and ultimately humans. In addition to physical presence, MPs can act as vectors for hazardous chemicals, additives, and pathogenic microorganisms, potentially amplifying their toxicological effects. Although the extent of human exposure through food consumption is still under investigation, recent studies have identified MPs in seafood, salt, drinking water, fruits, vegetables, and processed foods. The potential health implications include inflammation, oxidative stress, and disruption of cellular processes, though significant knowledge gaps remain regarding long-term exposure and dose-response relationships. This review highlights current findings on the occurrence, transfer, and risks of MPs within the food chain, emphasizing the need for standardized analytical methods and comprehensive risk assessment to better evaluate their impact on food safety and public health.