Gaby
Scientists have long been concerned about the accumulation of tiny synthetic particles known as microplastics in human organs. A new study from researchers at the University of New Mexico found that brain samples collected during recent autopsies contained significantly more microplastics than similar samples gathered about a decade ago. The team also measured higher concentrations of these petrochemical remnants in brain tissue than in samples from the kidneys and liver, said lead author Alexander Nikhart.
What Did the Researchers Report?
From 1950 to 2019, roughly 9 billion tons of plastic were produced worldwide for items such as single-use packaging, food containers, children’s toys, clothing, garden furniture, and more.
Since then, most of that material has broken down into very small particles, creating dust and fragments that spread across the globe. These micro- and nanoparticles have contaminated and continue to pollute everything around us. They have even been found in archaeological sites, the deepest ocean trenches, and in breast milk.
“The concentration of anthropogenic microplastics and nanoplastics in the environment, measuring 500 micrometers to 1 nanometer, has increased exponentially over the last half-century,” the scientists wrote in their report.
Nikhart’s team examined tissue samples from 52 human bodies autopsied between 2016 and 2024. Every tested sample contained plastic particles, according to ScienceAlert.
While the liver and kidney samples showed similar amounts of plastic, the concentration in brain samples was 30 times higher. That finding is surprising because the liver and kidneys help filter and break down waste in the body. The brain also has an extra layer of protection against pollutants: the blood-brain barrier, which is supposed to block many substances from entering.
The concentration of plastic in the analyzed tissues did not depend on age, ethnicity, or cause of death. However, samples from individuals diagnosed with dementia showed higher concentrations of particles than those without the condition.
They explained that atrophy of brain tissue, disruption of the integrity of the blood-brain barrier, and impaired elimination mechanisms are characteristics of dementia that can lead to increased concentrations of micro- and nanoplastics.
Nikhart and his colleagues joined other researchers who have been calling for more studies on how microplastics affect health.
Meanwhile, people keep ingesting plastic fragments as production rises.
“Plastic is a petrochemical product: a substance that is ultimately derived from oil and gas,” said Adam Hani, a global development researcher at the University of Exeter in the UK, who was not involved in the study.
The study was published in the journal Nature Medicine.
