A recent study by an international research team has uncovered that microplastics accumulate most significantly in the brain. The study found that the amount of plastic in the brain was up to 30 times higher than in other organs.
CNN and other international media reported that the research team, led by Matthew Campen, a professor of pharmacology at the University of New Mexico, analyzed autopsy samples from the liver, kidneys, and frontal cortex of the brain. These samples were collected from the Albuquerque morgue in New Mexico between 2016 and 2024. The findings, released through the National Institutes of Health (NIH), revealed that the brain contained the highest levels of microplastics among the organs studied. These results have not yet undergone peer review.
The study involved 92 cadavers over eight years and showed that microplastic levels increased across all organs. Specifically, microplastic concentration in the brain rose by approximately 50% during this period, with levels found to be 7 to 30 times higher than those in the liver and kidneys.
Microplastics are tiny plastic particles ranging from 5 mm to 1 µm (micrometer; one-millionth of a meter). Particles smaller than 1 µm are termed nanoplastics. A nanometer (nm) is one billionth of a meter.
Campen reported, “In brain tissues of healthy individuals aged 45 to 50, we found a concentration of microplastics at 4,800 µg (micrograms; one-millionth of a gram) per gram of brain tissue, constituting 0.5% of the brain’s weight.” He added, “Compared to samples from 2016, this represents an increase of about 50%, meaning today, 99.5% of our brains are brain tissue, with the remainder being plastic.”
The study also found that the microplastics in brain tissue are smaller than those in other organs. Campen explained, “The brain attracts tiny nanoplastics measuring 100 to 200 nm, whereas larger particles measuring 1 to 5 µm tend to accumulate in the liver and kidneys.”
The research team also discovered that plastics are drawn to fats, allowing them to enter organs through the bloodstream when consuming fatty foods. Given that the human brain is about 60% fat by weight and requires more fat than any other organ, this explains the higher concentration of plastics found in the brain.
Campen also noted, “In examining 12 brain samples from individuals who died of dementia, including Alzheimer’s disease, we found ten times more plastics than in healthy brains,” suggesting a potential link between increased microplastics in the brain and the rising incidence of dementia-related diseases.
