Tiny plastic particles are accumulating in human tissues at increasingly higher levels, a new study published in the journal Nature Medicine showed.
The study, led by Matthew Campen of the University of New Mexico, shows that there are significantly higher levels of plastic nano and micro particles in the liver and brain.
The research was carried out from deceased people in 2024 compared to those studied in 2016.
According to the study released on Tuesday, the contamination is particularly high in the brain, with levels up to 30 times higher than in other organs such as the liver or kidneys,.
It said that while micro plastics have previously been detected in organs like the lungs, intestines and even the placenta, conventional microscopy typically only identifies particles larger than five micrometers.
The authors of the study said this excluded smaller nano particles that may be present.
A micro metre is a thousandth of a millimetre, a nanometer a millionth of a millimetre.
Campen’s team employed advanced infrared and electron microscopy, which has allowed them to detect these smaller particles with greater accuracy.
The researchers analysed tissue samples from 24 deceased individuals in 2024 and compared them with 28 samples from 2016.
While the levels of plastic nano and micro particles in the kidneys remained largely unchanged, the liver and brain showed increases,particularly high levels in people with dementia
The study also identified alarming levels of micro plastics in the brains of people diagnosed with dementia.
Twelve (12) brain samples were collected between 2019 and 2024, contained between 12,000 and 48,000 micrograms of plastic per gram of tissue.
However, the researchers said that these findings are associative and do not establish a direct cause-and-effect relationship.
The team also analysed the types of plastic found, with polyethylene, the plastic commonly used in bottles and packaging found to be the most prevalent.
It accounted for 40 to 65per cent of the plastic detected in the liver and kidneys, and up to 75 per cent in the brain.
The researchers caution that some of the differences observed in brain tissue could be attributed to geographic factors, as the samples were collected from New Mexico and the U.S. East Coast.
They stressed the need for larger-scale; longer-term studies to further explore the effects of micro and nano plastic accumulation, particularly on neurological health.(dpa/NAN)
