According to Smithsonian Magazine (emphasis added):
The human brain may contain up to a spoon’s worth of tiny plastic shards—not a spoonful, but the same weight (about seven grams) as a plastic spoon, according to new findings published Monday in the journal Nature Medicine.
Researchers detected these “almost unbelievable” levels of microplastics and nanoplastics in the brains of human cadavers, says study co-author Andrew West, a neuroscientist at Duke University, to Science News’ Laura Sanders. “In fact, I didn’t believe it until I saw all the data.”
Based on their analysis, the amount of microplastics in the human brain appears to be increasing over time: Concentrations rose by roughly 50 percent between 2016 and 2024.
The researchers also found much higher levels of microplastics in brain tissue than in liver and kidney tissue. And microplastic concentrations were also higher in the brains of deceased patients who had been diagnosed with dementia compared to the brains of deceased individuals without dementia.
I rarely buy plastic cutlery, but I’ve got a drawer full of fast-food utensils just waiting for their moment. I wanted to see if a spoon really weighed 7 grams, so I opened a package and weighed one. To my surprise, it was only 4 grams. After I broke a tine off of a plastic fork and added it to the scale, I had 7 grams of plastic.
Look at that. A spoon, plus most of a fork. In your brain.
“I have yet to encounter a single human being who says, ‘There’s a bunch of plastic in my brain and I’m totally cool with that,’” says study co-author Matthew Campen, a toxicologist at the University of New Mexico, in a statement.