A plastic spoon’s worth of plastic is inside your brain, researchers warned on Tuesday, showing alarming new evidence about microplastic accumulation in human brain tissue.
Published in the journal Brain Medicine, the research revealed that human brains contain approximately a spoon's worth of microplastics and nanoplastics (MNPs), with levels 3-5 times higher in individuals with documented dementia diagnoses.
More concerning still, brain tissues showed 7-30 times higher concentrations of MNPs compared to other organs like the liver or kidney.
"The dramatic increase in brain microplastic concentrations over just eight years, from 2016 to 2024, is particularly alarming," said Dr Nicholas Fabiano from the University of Ottawa's Department of Psychiatry and lead author of the commentary. "This rise mirrors the exponential increase we're seeing in environmental microplastic levels,” he mentioned.
Of particular concern are particles smaller than 200 nanometers, predominantly composed of polyethylene, which show notable deposition in cerebrovascular walls and immune cells.
This size allows them to potentially cross the blood-brain barrier, raising questions about their role in neurological conditions.
The commentary said that switching from bottled to filtered tap water alone could reduce microplastic intake from 90,000 to 4,000 particles per year.
"Bottled water alone can expose people to nearly as many microplastic particles annually as all ingested and inhaled sources combined," said Dr Brandon Luu, an Internal Medicine Resident at the University of Toronto.
Switching to tap water could reduce this exposure by almost 90 per cent, making it one of the simplest ways to cut down on microplastic intake.
Other significant sources include plastic tea bags, which can release millions of micro and nano-sized particles per brewing session.
Heating food in plastic containers — especially in the microwave — can release substantial amounts of microplastics and nanoplastics, said researchers.
"Avoiding plastic food storage and using glass or stainless-steel alternatives is a small but meaningful step in limiting exposure. While these changes make sense, we still need research to confirm whether lowering intake leads to reduced accumulation in human tissues,” said Dr Luu.