Scientists find microplastics in brain tissue on human noses

Microplastics are inevitable. These tiny plastic particles Ancient ruinsNewly fallen Antarctic Snowat the top Everest And deep inside Mariana TrenchIn the human body, blood, Baby poop, placenta and lung.

The scientists have now found the microscopic contaminants in brain tissue as well, specifically in the olfactory bulb, located above the nose. They published their findings Monday in the journal Neuroscience. JAMA Network Open.

Humans have two Olfactory bulb Located in ForebrainThe olfactory bulbs are connected to each nasal cavity by the olfactory nerves. They are responsible for detecting and processing scents and odors, and transmitting information from the nose to the brain.

Microplastics are Found in the human brainaccording to Recent Research The new findings, which have not yet been peer-reviewed, have raised concerns among researchers that microplastics could enter the brain via the olfactory pathway and reach brain regions beyond the olfactory bulb.

“one time [the olfactory bulb]”In some cases, translocation to other areas of the brain may occur,” said a co-author of the study. Luis Fernando Amato-LorenzoHe is an environmental scientist at the Free University of Berlin. CNN“How particles move depends on several factors, including the shape of the particle, whether it's a fiber or debris, how big the particle is, and the body's defense mechanisms,” says Sandy LaMotte of the Department of Environmental Health at the University of Maryland.

For the study, the team harvested olfactory bulb tissue from 15 human cadavers, who died between the ages of 33 and 100.

Eight of the samples Microplasticsor plastic fragments less than 5 millimeters in length. The researchers found a total of 16 plastic fibers and particles made of polypropylene, polyamide, nylon, and polyethylene vinyl acetate. The most common were polypropyleneIt is a type of plastic that is widely used in clothing, furniture, rugs, packaging materials, etc.

The researchers did not analyze the samples. Nanoplasticswhich is an even smaller particle 1,000 times smaller The microplastics are smaller than the width of a human hair, but the ones they found were “much smaller than those found in several other studies that have found their presence in human organs, such as the placenta, kidneys and liver,” Amat Lourenço told CNN.

The finding came as no surprise to the team, given that microplastics are everywhere — and since the nose's job is to keep dust, particles, and other invaders from reaching the lungs, it makes sense that nasal tissue would also trap plastic debris.

However, it is unclear whether microplastics reach the brain via the olfactory pathway. Brain-eating amoeba Naegleria fowleriit can also enter the brain this way, but such instances are rare.

“There is evidence that very small airborne particles can travel to the brain via the olfactory bulb, but it is not known whether this is the primary route of transport of materials to the brain,” they said. Matthew Campen“The study is a toxicologist at the University of New Mexico, who was not involved in the study,” NBC NewsCaitlin Sullivan. Kampen said, Preprint A study has found the presence of microplastics in the human brain.

The researchers also couldn't determine why microplastics were found in some bodies and not others, though one possible explanation is that inflammation of the lining of the nasal passages, called the mucosa, could make it easier for plastic particles to enter the nasal tissue in some people but not others, according to CNN.

When microplastics enter the human body, they can have the following effects: Little knownHowever, some studies suggest that it may be harmful to human health.

Earlier this year, researchers found a link between microplastics in human arteries and an increased risk of heart disease. New England Journal of Medicine The incident, which occurred in March, “was the first time that the particles themselves were confirmed to have an effect on human health.” Philip LandriganThe Boston University pediatrician and epidemiologist was not involved in either of the recent studies. National GeographicTara Hael of will be performing in April.

“Until now, the conventional wisdom has been, 'The particles are there, but we don't know anything about what they're doing,'” he added. “This paper changes that.”