Microplastics reach human brain: Contains 10-20 times more of it than any other organ

Scientists have raised alarm after discovering microplastics in critical human organs, including the brain. They are calling for more stringent measures to control plastic pollution. A new study has found that a lot more microplastics are present in the human brain than in any other organ. The researchers described the brain as “one of the most plastic-polluted tissues yet sampled”.

Microplastics are pieces smaller than 5mm in diameter. They have already been found in several other human organs - lungs, placentas, livers, kidneys, reproductive organs, knee and elbow joints, blood vessels and bone marrow. Just last month, a study found microplastics in all 16 samples of bone marrow that were examined.

In the latest study done by the National Institutes of Health, they found that microplastics are now accumulating in human brains.

Sedat Gündoğdu, who studies microplastics at Cukurova University in Turkey, told Guardian, that plastic pollution needs to be dealt with soon and following the new research, “it is now imperative to declare a global emergency”.

They studied the livers, kidneys and brains of autopsied bodies and discovered microplastics in all of them. However, what is most concerning is that they found 10 to 20 times more microplastics in the 91 brain samples than the other organs.

The study’s lead author, Matthew Campen, a toxicologist and professor of pharmaceutical sciences at the University of New Mexico, admitted that the results were shocking.

Microplastics in brain

Twenty-four of the brains collected in early 2024, measured on average about 0.5 per cent plastic by weight. “It’s pretty alarming. There’s much more plastic in our brains than I ever would have imagined or been comfortable with," Campen said.

Another disturbing discovery was the quantity of microplastics seems to be increasing over time. Brain samples from 2024 had about 50% higher microplastics as compared to samples that date to 2016.

The study that is yet to be peer-reviewed and printed also hints at a possible link between dementia and Alzheimer’s disease. The brain samples of 12 people who had died of the two diseases, had up to 10 times more plastic by weight than samples from healthier individuals. However, this part of the study hasn't been published online yet, as per the Guardian.

Another recent study done in China found microplastics in the membranous lining of hip or knee joints of 45 patients who were undergoing hip or knee surgery. Microplastics were also found in all 23 human and 47 canine testicles in a study conducted in May.