I’ve Got Microplastics On My Brain — And So Do You – CleanTechnica

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Last Updated on: 21st February 2025, 08:15 pm

What’s this? Microplastics entering human brains? Yup. The results of a new study published in Nature Medicine point out that tiny fragments of plastic are passing the blood-brain barrier and entering into human brains. Moreover, the amount of microplastics in the brain appears to be increasing over time.

“There are no control groups,” toxicologist Matthew Campen, one of the authors of Bioaccumulation of Microplastics in Decedent Human Brains, noted. “Everyone is exposed.” Additionally, Campen revealed that the brain is “one of the most plastic-polluted tissues yet sampled.”

What are microplastics? Microplastics are minuscule dots of plastic — less than five millimeters in size, or smaller than a pencil eraser — that are either manufactured or peel off plastic objects. Microplastics, which form from the breakdown of larger plastics and also are used to create many commercial products, are a source of environmental pollution that are known to affect oceans and marine life. The influx of plastics entering the world’s oceans, without immediate action to reverse the current trend, is expected to increase roughly 2.5 times from 2016 to 2040.

What are nanoplastics? Nanoplastics are even smaller and can be a fraction of the width of a human hair. Most of the microplastics found in brains in the study were on the nano scale.

Where do microplastics and nanoplastics come from? Determining precisely what these plastics are doing inside people and whether they’re harmful has been difficult. Microplastics are everywhere. Earlier this month in Nature, Campen outlined how it’s been difficult to determine which microplastics people are exposed to, how they’re exposed, and which particles make their way into the nooks and crannies of the body.

Is this study the first time we realized that microplastics are entering the body? No, but it’s taken a while. The term “microplastics” was coined 20 years ago, but only in the past 10 years have researchers progressed from studying the particles in the environment and animals to gauging their effects on human health. It’s been known that many particles are moving into the human body. Microplastics had already been identified in the liver, placenta, blood, testicles, and even certain arteries that lead to the heart.

Why have microplastics become so insidious in the past several years? The amount of plastics produced globally doubles every 10 to 15 years. Over the years scientists have come to realize that many plastic items (plastic bags, water bottles, tires, polyester or synthetic clothing) can shed small fragments or fibers that make their way into air, food and water. In fact, the concentration of microplastics in analyzed brains rose by about 50% from 2016 to 2024.

How many microplastics are actually in contemporary human brains? Researchers estimate that the average brain studied had about seven grams of microplastics in it, or a little more than the weight of a plastic spoon. The present data suggest a trend of increasing microplastic concentrations in the brain and liver, the majority of which appear to be nanoplastic shards or flakes.

What specific findings did the researchers have about microplastics and the brain? The Nature Medicine study shows that the pieces of plastic are reaching deeper into the frontal cortex. Last year, a group of researchers found microplastics in the olfactory bulb, or the part of the brain that processes smells. The particles were present in eight of the 15 brains studied. They found small shards or flakes in unexpected shapes, which could mean different health effects. “I don’t know how much more plastic our brain can stuff in without it causing some problems,” Campen said.

How did scientists come up with their conclusions about microplastics and the brain during this study? For the new study, scientists analyzed 52 brain specimens: 28 that were autopsied in 2016 and 24 that were autopsied in 2024. They found microplastics in every sample, but there were significantly higher concentrations of microplastics in those from 2024.

How did those results differ from previous samples? Researchers obtained additional brain samples going back to 1997 and found that they followed the same trend: More recent samples had much higher numbers of microplastics. The paper also showed that the brain appears to be more susceptible to microplastics than other organs — brain samples had seven to 30 times as much microplastics in them as liver and kidney samples.

Do demographics change the study data? Plastic concentrations in these decedent tissues were not influenced by age, sex, race/ethnicity or cause of death. Specifically, the researchers found no correlation with how old the person was when they died. The scientists also examined the brains of 12 deceased patients diagnosed with dementia and found that they had three to five times as much microplastics as normal brains.

What recommendations should we take away from the data about microplastics entering the human body? The potentially dangerous effects on people’s health and mental acuity are too serious to be ignored. Leading researchers have called for more urgent actions to rein in plastic pollution.

What research is the US federal government conducting on microplastics and the human body? There are currently no governmental standards for plastic particles in food or water in the US. The Environmental Protection Agency (EPA) had been working on crafting guidelines for measuring them and had been giving out grants since 2018 to develop new ways to quickly detect and quantify them. That being said, over the years the FDA has not fully embraced the reality of microplastics entering the human body as described on their website. To wit:

“Current scientific evidence does not demonstrate that the levels of microplastics or nanoplastics detected in foods pose a risk to human health. Additionally, because there are no standardized methods for how to detect, quantify, or characterize microplastics and nanoplastics, many of the scientific studies have used methods of variable, questionable, and/or limited accuracy and specificity.”

Add to that skepticism the enormous amounts of federal funding cuts currently taking place under the Trump administration, and there’s no way of knowing if microplastic absorption in the human body will get attention from the US federal government that it warrants. A much more robust 3.0 approach is needed if we are to mitigate the ecological consequences of these hazardous substances.