Nanoplastics Found In The Brain

by Mila McManus, MD

Researchers found 2,000 milligrams of nanoplastics in brain tissues, equivalent to the amount found in a plastic sandwich baggie. — Is there a baggie in your brain?

In a recently published study, researchers found 2,000 milligrams of nanoplastics in the frontal cortex of the brain, equivalent to the amount found in a plastic sandwich baggie. That’s really disturbing!

Nature Medicine published the study that examined tissue concentrations of nano- and microplastics in the livers, kidneys, and brains of thirty deceased individuals. The autopsy study gathered tissues from biobanks around the country, half of whom died in 2016, and the other half died in 2024. Another startling finding was the dramatically higher concentration of nanoplastics in the brains of those who died in 2024 compared to their predecessors eight years earlier. There were no differences in plastic concentrations between genders, ethnicity, or age. The only factor significantly correlated with the amount of plastic in the brain was the year the individuals died. The more recently they died, the more plastic was found.

Microplastics and nanoplastics – tiny bits of plastic as small as 1 nanometer across – have been detected in various human tissues, including the lungs, placenta, liver, kidneys, and plaques in the carotid arteries. This adds a poignant twist to the idea that we are what we eat and drink. Clearly, we are increasingly eating and drinking plastic!

The researchers complemented traditional light microscopy with gas-chromatography mass-spectroscopy to identify particles that are too small to be seen under a conventional microscope. These instruments were key to understanding what is going on in the brain. The blood-brain barrier effectively prevented the larger microplastic pieces from entering. However, the very small nanoplastic pieces manage to pass through and become lodged in the brain. A subset of the individuals studied had dementia at the time of death. Plastic levels were drastically higher in the brains of that group, equating to 10 sandwich bags!

The researchers were also able to identify the type of plastic present in the brain, which helped determine the source. There are three main types of plastic. Polystyrene is commonly found in packing peanuts and used in Styrofoam cups and plates. Polyethylene is used in plastic zip-top bags, water bottles, storage containers, cutting boards, and plastic wraps. Polypropylene is found in crates, bottles, and jars. By and large, across all the tissues, the plastic found was polyethylene, the most commonly produced plastic. It does not biodegrade and is everywhere.

While it is almost impossible to avoid plastics and other toxins in the environment today, there is no doubt that improved health can be achieved by controlling as many variables as possible. A study in Environmental Science & Technology estimated that individuals who drink most of their water from plastic bottles ingest an additional 90,000 particles of microplastics per year, compared to 4,000 for those who consume only tap water. That’s a big difference. It’s an easy fix to bring a reusable glass or stainless-steel bottle with you.

Reduce your usage of plastic everywhere possible.

Don’t have a baggie brain. Be well.

References:

Nihart, A.J., Garcia, M.A., El Hayek, E. et al. Bioaccumulation of microplastics in decedent human brains. Nat Med (2025). https://doi.org/10.1038/s41591-024-03453-1

Micro(nano)plastics in the Human Body: Sources, Occurrences, Fates, and Health Risks, Penghui Li and Jingfu Liu, Environmental Science & Technology 2024 58 (7), 3065-3078, DOI: 10.1021/acs.est.3c08902

Plastic Cutting Boards: Are Yours Safe?

by Mila McManus, MD

Research demonstrates plastics is a public health concern and may be one of many factors contributing to chronic inflammation and disease.

Mounting research is demonstrating that our chronic exposure to plastics is a public health concern and may be one of many factors contributing to chronic inflammation and disease. From bottled water to kitchen cutting boards, everyone can take steps to reduce and minimize exposure and ingestion of microplastics.

According to one study, scientists cut carrots on two types of plastic cutting boards, one made with polypropylene and the other with polyethylene. Each time the boards were used to cut carrots, the scientist measured up to as many as 1,114 microplastic particles from the board on the carrots. Microplastic particles are pieces of plastic less than five millimeters long. They estimated that over the course of one year, 50 grams of microplastics, roughly equivalent to ten plastic credit cards is released onto the food being prepped.

Microplastics are being found in human lungs, blood, and even in the placenta. These plastics have chemical additives in them which disrupt the endocrine/hormonal and reproductive system. All plastic objects can become a source of microplastic ingestion once they begin to degrade. Most plastics don’t break down in the environment, but they do break apart into these microparticles which then can absorb chemical pollutants and microorganisms. In other words, microplastic particles are a vehicle on which other chemicals can hitch a ride, enter the body, and wreak havoc. Both the plastic and its passengers pose a health threat.

Here are a few good places to begin reducing exposure to microplastics:

Replace plastic cutting boards with glass, marble, bamboo, or solid wood boards.
Replace all of your plastic utensils and kitchenware with glass, stainless steel, and silicone.
Avoid drinking from disposable plastic water bottles. These bottles, if exposed to warm, humid, sunny environments (think outside of the grocery pick up area of your favorite grocer, or on non-airconditioned delivery trucks, or in your car on a hot day), degrade very easily in response to temperature change or mechanical stress. This causes harmful chemicals to end up in the water you’re drinking from plastic bottles.
Filter your city tap water. Go to ewg.org for information about water contamination, problems, solutions, and recommendations.

Avoid Plastics. Be Wise. Be Well.

References:

Culpepper, J.R. Making meals without microplastics: Tips to safer cutting boards. Environmental Working Group, October 20, 2023.

https://www.sciencedirect.com/science/article/abs/pii/Soo45653522007603#sec3.1