Microplastic and brain: risks to monitor

What do microplastics do to our brain? However, The answer is far from being decided. For example, but the question cannot be eluded while studies show more and more clearly that these particles accumulate in our nervous system.

A study in early 2025. In addition, notably aroused great attention and constitutes a significant advance in the evaluation of the exposure of our brains to microplastics. Nevertheless, Published in Nature Medicinethis work concluded that a “upward trend in microplastic concentration in the brain and the liver”.

These conclusions have largely contributed to opening a new chapter in broader questions around the health effects of these tiny plastic particles: less than five millimeters when it comes to microplastics. Meanwhile, 1,000 times less when we talk about nanoplastics.

They are omnipresent in the environment and. therefore, inhaled or ingested daily by each of us, which makes it a microplastic brain: risks monitor subject at the heart of the negotiations which reopen Tuesday in Geneva to lead to a treaty against plastic pollution.

Before the brain. Nevertheless, scientists have already found microplastics in recent years in the lungs, the heart, the liver, the kidneys, or even in the placenta and the blood.
The study published in Nature Medicine It was made from the autopsy of around fifty people who died in the. American state of New Mexico. Part of the sample had died in 2016, the other in 2024. This work concluded that the systematic presence of microplasticism in the brain. as well as a clear increase between the two dates.

A brain could thus contain the equivalent of a teaspoon of microplastics. had imagined Matthew Capen, principal researcher of the study. The American toxicologist had also estimated that researchers could extract approximately 10 grams of plastic from a removed brain.
A figure likely to microplastic brain: risks monitor make an impression. but some specialists emphasize that the study cannot be self-sufficient, given the small number of people and their geographic concentration in one place.

“Even if these are interesting results. they must be interpreted with caution,” warns the researcher Theodore Henry, a specialist in environmental toxicology at the Scottish University Heriot-Watt, with AFP.
And “at this stage, speculation about possible health effects venture far beyond the evidence,” he puts it into perspective.

Likewise. Oliver Jones, professor of chemistry at the Australian University Rmit, prefers to remain cautious: “If – and it is a big one if in my opinion – there are microplastics in our brain, there is currently no evidence of harmful”, he underlines to AFP.

Thrombosis in mice

However. many researchers consider that this study largely justifies to question the effects of microplastics on our brain, while, in recent years, first elements have appeared microplastic brain: risks monitor on other health risks.

A study published in 2024 in the New England Journal of Medicine shows an association between the accumulation of these particles in blood vessels. an increased risk of heart attack, stroke, even death, in some people with atherosclerosis, a disease affecting the arteries.

Currently. no study of this type exists for the brain and, more broadly, the neurological risks associated with microplastics in humans. But toxicologists call for the precautionary principle. citing the example of other types of pollution such as that with fine particles in the air.

“What is worrying for the brain is that fine particles are the chemical component of the exhibition”. that is to say all of the environmental factors to which a person is exposed, “who is most associated with Alzheimer’s disease”, underlines the French toxicologist Xavier Coumoul, professor at Paris Cité University.

Would it be the same for microplastics? The microplastic brain: risks monitor answer is not obvious since the fine particles are of a “quite different nature”, as Mr. COUMOUL notes, but it deserves more research, in particular experiences on animals like mice.

Still few. these studies are nevertheless beginning to give some results, even if they cannot alleviate similar effects in humans alone.
Posted in January in the journal Science Advancesan experience. for example, highlighted in mice the deleterious effects of microplastics whose presence was detected live in the brain by advanced imaging techniques.
These microplastics “can cause brain thromboses (…) and generate neurocomptal disorders”, conclude the authors of this study conducted in China.

By Julien Dury/AFP