Microplastics and Nanoplastics in Human Brains and Accessory Tissues

Introduction: Microplastics and nanoplastics (MNPs), a growing concern worldwide, are emerging contaminants that may infiltrate various human tissues. However, the ability of MNPs to penetrate the blood-brain barrier and deposit in the human brain and accessory tissues remains unclear.

Methods: In this first-of-its-kind, pre-clinical study, we analyzed 75 samples including human brains and accessory tissue samples from 50 neurosurgical patients, using Micro-Fourier transform infrared spectroscopy, scanning electron microscopy, and energy dispersive X-ray.

Results: Our findings confirmed the presence of MNPs in 40.0% (30/75) samples, spanning various tissues including the brain, tumor, vascular wall, plaque, extracerebral tissues, and cerebrospinal fluid. Notably, MNPs were not detected in any blood samples. Intracranial tumors had the highest MNP detection rate (11/15, 73.3%), followed by arteriovenous malformations (3/5, 60.0%) and plaques (6/11, 54.5%). The average MNP size was 17.3 μm, with polyethylene terephthalate being the most common type (51.2%). Interestingly, patients without detectable MNPs had a higher prevalence of conditions like diabetes and elevated white blood cell and glucose levels. No significant differences in postoperative complications were observed.

Conclusion : This study provides the first evidence of MNP deposition in the human brains and accessory tissues. Further research is crucial to understand how MNPs reach the brain and their potential impact on neurological health.