Microplastics may accelerate neurodegenerative processes through five main brain-harming pathways: immune activation, oxidative stress, disruption of the blood–brain barrier, mitochondrial impairment, and direct neuronal damage.

The research notes potential links to Alzheimer's disease via beta-amyloid and tau buildup and to Parkinson's disease via alpha-synuclein aggregation and dopaminergic neuron damage, while stressing that a direct causal link needs further study.

Mitochondrial disruption lowers ATP production, weakening neuron activity; combined with inflammation and oxidative stress, this could contribute to both Alzheimer’s and Parkinson’s disease features.

The joint study is conducted by teams from the University of Technology Sydney and Auburn University, including collaborators Murali Dhanasekaran, Keshav Raj Paudel, and Brian Oliver.

The international collaboration emphasizes that more work is needed to establish causation, but calls for reducing plastic exposure in the meantime.

The work originates from an open-access paper in Molecular and Cellular Biochemistry, with authors from UTS and Auburn University, and Neuroscience News summarized its context and implications.

Researchers urge reducing plastic exposure as a precautionary public health measure, suggesting practical steps and hoping findings inform policy to curb plastic production and improve waste management.

Concrete recommendations include avoiding plastic containers and cutting boards, opting for natural fibers, cutting dryer usage, and limiting processed and packaged foods to lower long-term neurological risk.

Microplastics are ingested from seafood, salt, processed foods, tea bags, plastics in daily life, soil-grown foods, clothing fibers, and dust, with an estimated average intake of about 250 grams per adult annually, though most are cleared with some accumulation in organs including the brain.

In addition to ingestion sources, microplastics can accumulate in organs such as the brain despite clearance from the body.

Public health relevance centers on potentially lowering long-term neurological risk by reducing microplastic exposure and guiding policy and behavior changes.

Past UTS work has examined inhalation and lung deposition of microplastics, with Paudel focusing on respiratory impacts as part of ongoing research.

UTS and Auburn researchers, led by first author Alexander Chi Wang Siu, are investigating brain cell function under microplastic exposure in collaboration with Dua and Dr. Keshav Raj Paudel.

A systematic review from UTS and Auburn University highlights brain accumulation and interactions with neurodegenerative mechanisms, while stopping short of proving direct causation.