Scientists find microplastics being sucked into the brain

[New Sancai Compilation and First Release] Scientists have detected the presence of tiny plastic particles in the human brain for the first time.

Researchers in Germany and Brazil said microplastics were detected in the brain's olfactory centers (olfactory bulbs) in eight of 15 adult autopsies.

These particles are likely inhaled during a lifetime, as tiny floating microplastics are ubiquitous in the air.

Although microplastics have been found in human lungs, intestines, livers, blood, testicles and even semen, it has long been thought that the body's protective blood-brain barrier may keep these particles out of the brain.

However, a team led by Luis Fernando Amato-Lourenco of Freie Universität Berlin and Thais Mauad, an associate professor of pathology at the University of São Paulo in Brazil, said that this A new study shows that there is a "potential pathway for the transfer of microplastics to the brain" through the olfactory bulb.

The team published their findings on September 16 in the journal JAMA Network Open.

"As smaller nanoplastics enter the human body more easily, the total level of plastic particles may be higher," Moad said in a press release from the Plastics Health Council, an advocacy group that advocates for reducing plastic use and helps fund the process. organization for the new study.

"What is concerning is the ability of these particles to be internalized by cells and alter the function of our bodies," Moad added.

The new study involved brain tissue from 15 routine autopsies of deceased residents of São Paulo, Brazil. The ages at death ranged from 33 to 100 years (mean age 69.5 years).

Researchers reported that "a total of 16 synthetic polymer [plastic] particles and fibers were found" in the olfactory bulbs of the brains of eight of the 15 people who died.

Nearly 44% of plastics are polypropylene – one of the most common plastics used in everything from packaging to clothing and home accessories.

The research team said this showed that "the indoor environment is a major source of inhaled microplastics."

So how do these tiny fragments invade the brain?

Amato-Lorenco and colleagues suggest that the nasal mucosa, located on the outside of the brain, may interact with the cerebrospinal fluid, allowing microplastics to enter the olfactory bulb through tiny "holes" in the bony structure of the area.

"So when you breathe through your nose, your olfactory nerves directly sample particles and respond to the particles you inhale as a direct sensory mechanism." Core of Medical Toxicology, Long Island Jewish Medical Center, New York Faculty member Dr. Wells Brambl said he was not involved in the study.

"The fact that there's no blood-brain barrier there, you have direct access to the brain, and on top of that, right above the olfactory nerves are the frontal and prefrontal lobes, which we think are the seats of consciousness," Bramble added.

The Brazilian researchers noted that other studies have shown that "ambient black carbon particles" from air pollution can be found in the olfactory bulbs and, in rare cases, the tiny amoeba that can cause fatal encephalitis.

They say the new data "expands the idea that not only black carbon but also microplastics accumulate in the human olfactory bulb."

Do these microplastics affect brain health? Amato-Lorenco's team says it's unclear yet, but the "potential" is there.

"Given the possible neurotoxic effects of microplastics in the brain and the widespread contamination of the environment by plastics, our findings should have implications for patients with neurodegenerative diseases such as Parkinson's disease, ALS, and other diseases," the researchers said. arousing people’s attention in the context of increasing disease rates.”

"My gut feeling is that having plastic in the brain is not good," Bramble said. "However, data from long-term prospective studies have not yet been conducted. Therefore, it is impossible to draw any firm conclusions."

Still, he said, "I think this study is very sobering because we need to start looking at this as a real public health problem long-term."

(Compiled by: Wang Jimin)

(Editor: Jiang Qiming)

(Source of the article: Compiled and published by New Sancai)