Plastamination in Human Brain: The Possible Role of Microplastics in Neuroinflammation and Parkinson’s Disease

Plastic contamination (plastamination) has become a pervasive environmental threat with growing implications for human health. Among plastic-derived contaminants, micro- and nano-plastics (MNPs) are of particular concern due to their persistence, widespread distribution, and capacity to interact with biological systems. Humans are exposed to MNPs through ingestion, inhalation, dermal contact, and maternal transfer, and these particles can cross biological barriers, including the blood–brain barrier, reaching the central nervous system. MNPs disrupt cellular homeostasis by inducing oxidative stress, mitochondrial dysfunction, and inflammation. In the brain, these processes drive glial activation and chronic neuroinflammation, which are closely associated with neuronal damage and neurological disorders, including Parkinson’s disease (PD). MNPs can also affect systemic pathways such as the gut–brain axis (GBA) and neuroendocrine regulation, suggesting broader physiological consequences. This narrative review synthesizes current evidence on the neurotoxic and pro-inflammatory potential of MNPs. Since MNPs may promote the aggregation of proteins implicated in neurodegeneration, such as alpha-synuclein, their possible role in PD is discussed. Despite several knowledge gaps, MNPs may be emerging environmental risk factors for brain health and neurodegenerative diseases such as PD. Nevertheless, there is a need for further studies in the field, standardized methodologies and longitudinal studies to implement effective mitigation strategies.