Neurotoxicity of Micro- and Nanoplastics: A Comprehensive Review of Central Nervous System Impacts

Micro- and nanoplastics (MNPs), originating from plastic wastes degradation, industrial processes, and textile fiber shedding, persist in the environment and act as carriers of hazardous substances, posing significant global health risks. Growing evidence links MNPs exposure to neurotoxicity; however, substantial knowledge gaps remain regarding their environmental distribution, cellular effects, and epidemiological consequences. This review systematically examines the sources and exposure pathways of MNPs, as well as their potential contribution to neurological disorders. It outlines key neurotoxic effects, including neuronal damage, synaptic dysfunction, blood-brain barrier disruption, neuroinflammation, and protein aggregation, which may contribute to cognitive decline and motor impairments. Additionally, it explores the underlying mechanisms of MNPs-induced toxicity, such as oxidative stress, immune responses, mitochondrial dysfunction, cell death signaling, and the gut-brain axis. Given the complexity of MNPs interactions, the study highlights the need for future research on coexposure effects with other pollutants and their impact on MNPs toxicity. Finally, this article advocates for stricter MNPs pollution control, advancements in detection technologies, and a deeper understanding of neurotoxic mechanisms, emphasizing the necessity of interdisciplinary collaboration to assess and mitigate associated health risks.