Research progress in mechanisms of neurotoxicity induced by micro(nano)plastic exposure

Microplastics (MPs) and nanoplastics (NPs) can accumulate in the nervous system via various exposure routes, including ingestion, inhalation, and dermal contact. Such accumulation may contribute to neurotoxic outcomes, including alterations in neuronal structure, inhibition of neurodevelopment, as well as cognitive, behavioral, and neurodegenerative diseases. This review provides a comprehensive examination of the potential mechanisms through which MPs and NPs may exert neurotoxic effects. These mechanisms include: (1) cellular-level disruptions such as OS, mitochondrial dysfunction, and DNA damage; (2) neurochemical alterations involving neurotransmitter imbalances and inhibition of AChE activity; and (3) structural and systemic effects such as BBB disruption, inflammatory responses, and gut–brain axis-mediated neurotoxicity. Building upon these mechanistic insights, recent studies have explored various agents that may mitigate neurotoxicity induced by MPs/NPs, These substances may exert protective effects through multiple pathways, including reducing oxidative stress (e.g. curcumin), suppressing inflammation (e.g. probiotics), and preserving BBB integrity (e.g. Camellia pollen). However, there are still gaps in research regarding chronic low-dose exposure, interactions with co-pollutants, and susceptible populations. Future research should focus on actual exposure scenarios to more accurately assess the risk of neurotoxicity.