Brain Tissue May Contain Higher Amounts Of Microplastics Than Other Organs: Study
Brain samples contained 10 times more microplastics than other organs.
The brain may contain higher -- and more significant -- amounts of microplastics than other organs in the body, according to a new study.
Researchers from the University of New Mexico Health Sciences Center, Oklahoma State University, Duke University and La Universidad del Valle en Cali in Colombia analyzed brain, liver and kidney samples from 47 cadavers.
The results, published Monday in the journal Nature Medicine, found that brain samples contained far more microplastics than the other organs -- roughly 10 times more. The average amount, 4,800 micrograms per gram of microplastics in brain tissue, was found to be equivalent to the amount found in a standard plastic spoon, according to the study.
Dr. Stephanie Widmer, a board-certified medical toxicologist and emergency medicine physician, who was not involved in the study, told ABC News that the study's findings are not yet cause for major concern.
"This is certainly not the first study of its kind," she said. "We know that microplastics are really, really prevalent in our environment, and it's not the first study to show that microplastics are being found in human tissue."
"Again, we don't know the exact human health effects our plastics have," she continued. "We don't really know what to make of it. I definitely think that people should try to limit plastic use wherever they can and only use single use plastics one time."
It is also not yet known what specific health risk this amount of microplastics inside a person's blood stream could potentially have, the study says.
Widmer added that although there is some evidence the chemicals in microplastics can have negative effects on human health, it's unclear what the full impacts are, and more research needs to be conducted.
The study also looked at brain samples from individuals with dementia and found higher levels of microplastics, which it said may have accumulated in blood vessel walls and immune cells.
Widmer said the study does not prove that microplastics cause diseases, nor does it explain how they enter the brain.
"[The authors are] not saying that this finding means that microplastics cause dementia," she said. "They're not saying that in any way, shape or form. It's a finding that's there and more follow up research needs to be done to really know what to make of it."
The study also found microplastic levels in the brain may possibly have increased by 50% since the last time a similar study was conducted in 2016, which it says could indicate rising environmental exposure of microplastics.
Polyethylene, the most common type of plastic -- which is found in everything from plastic containers to flooring material to medical devices -- made up 75% of the microplastics that were found in brain samples, the study showed.
The authors say that detection methods used may have missed tinier particles or misidentified materials and the small sample size also limits conclusions about if, how and when the body handles these plastics.
"This whole field is really in its infancy," Widmer said. "While there is evidence that the microplastic burden in human tissue is high, these numbers may not be exact, and the authors recognize that."