0
0
Tiny plastic particles are now found not only in the most remote regions of the world, but also almost everywhere in the human body. Tissue analyses of deceased individuals now show how much pollution has increased over the years. Higher amounts accumulate in the brain than in the kidneys and liver.
Over the past 50 years, environmental pollution from tiny plastic particles has increased worldwide. The nano- and microparticles range in size from one nanometer to 500 micrometers. According to estimates, humans ingest up to five grams of them every week – through the air, skin, or food. This allows microplastics to enter the bloodstream and organs.
The health consequences of these foreign bodies in the human organism and the quantities at which they could be harmful have not yet been fully clarified. In the short term, the microparticles could cause functional disorders in the cardiovascular system, for example, and in the long term, they could promote the development of chronic diseases; chronic inflammation, respiratory diseases, and metabolic problems, among other things, are associated with them.
A recent study on mice shed light on what they could do to the brain: the particles are “eaten” by immune cells. The “scavenger cells” can then clump together, clog blood vessels, and possibly trigger thrombosis.
Exposure is increasing
What is clear, in any case, is that exposure has also increased in the human body in recent years. This is illustrated by a study just published in the journal Nature Medicine. Researchers led by Matthew J. Campen of the University of New Mexico Health Sciences analyzed tissue from deceased individuals in Mexico and the eastern United States, including liver, kidney, and brain tissue. The samples were taken in 2016 and 2024. New methods made it possible to locate particles smaller than five micrometers. Previous studies were only of limited significance in this regard.
Microplastics accumulate in the brain
The contamination in kidney tissue was similarly high in both years, averaging 538 micrograms of microplastics per gram in 2016 and 666 micrograms per gram in 2024. As the authors write, this is more than has been measured in previous tissue samples, for example, from the placenta (an average of 68 micrograms) or the testicles (299 micrograms). In liver tissue, the average concentration rose from around 142 (2016) to 465 (2024) micrograms per gram. The amounts in the brain were many times higher than in the liver and kidneys: in 2016, and the average was 3,345 micrograms, and in 2024, 4,917 micrograms per gram.
The team also used chemical analysis to determine the composition of the plastic. The most common type found was polyethene, which is used for films and bottles. It accounted for 40 to 65 percent of the plastic in the liver and kidneys and as much as 75 percent in the brain.
Microplastics and dementia?
All samples show that the concentration in all three organs has increased over the eight years. In a further step, the team compared the contamination of brain tissue with older samples from 1997 to 2013. This confirmed the general increase in microplastics in the human brain over the last few decades.
An even higher concentration of microplastics and nanoplastics was found in the brains of twelve people diagnosed with dementia. The samples contained between 12,000 and 48,000 micrograms of plastic per gram of tissue. As the researchers emphasize, this is purely a statistical correlation for the time being; a causal link has yet to be proven. However, given the high and increasing levels of pollution affecting the human brain, there is an urgent need to investigate in larger samples whether and how these tiny particles can actually cause damage there.
- source: orf.at/picture: pixabay.com
This post has already been read 54 times!
