Abstract

Microplastics (MPs), are small plastic particles less than 5 mm. They are pervasive environmental contaminants with emerging neurotoxic potential. MPs are generated from daily used products such as food packaging, textiles, and tire debris and comprise of various synthetic polymers, plasticizing additives (e.g bisphenol A and phthalates), and adsorbed pollutants. Human exposure to MPs occurs daily through ingestion, inhalation, and dermal contact. The potential of MP to cause neurological defects emanates from its capacity to traverse the blood-brain barrier (BBB), to induce oxidative stress, neuroinflammation, and neurotransmitter dysregulation, ultimately compromising neuronal integrity and predisposing individuals to neurodegenerative disorders including Alzheimer’s and Parkinson’s diseases. This review consolidates current experimental and epidemiological evidence on the sources, exposure routes, and core neurotoxic mechanisms of MPs, and proposes targeted mitigation strategies. An integrated understanding of these dimensions is essential for developing evidence-based environmental and public health policies.

Keywords: Microplastics, Brain health, Blood-brain barrier, Neuroinflammation, Neurodegeneration, Oxidative stress