Topline
Microplastics have been found in brain tissue above the nose, suggesting a likely passageway for microscopic plastic shards and fibers to enter the brain after already being discovered in nearly every organ in the human body, according to a new study published Monday in the journal JAMA Network Open.
Microscopic plastic shards and fibers have been found in nearly every organ in the human body.
Key Facts
Researchers analyzed the brains of 15 cadavers—12 men and three women who died between the ages of 33 and 100—and found eight contained microplastics in the tissue of the olfactory bulb, the part of the brain that processes smell, the study said.
The presence of microplastics on the olfactory bulb indicates a “potential pathway” for microplastics to make their way to other parts of the brain, researchers said.
Early findings in a study published in May suggested the brain contained up to 20 times more microplastic than other organs and could account for 0.5% of the brain’s mass, though it was not immediately known where it was accumulating.
The study’s results “should raise concern” about how microplastics could result in an increased risk of neurodegenerative diseases, researchers said.
Sixteen plastic fibers and particles were found in the eight brains and ranged from 5.5 micrometers—smaller than the diameter of a human red blood cell—to 26.4 micrometers in size.
It is not immediately clear why or how the brain tissue of some cadavers were exposed to microplastics while others weren’t, the study noted.
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Surprising Fact
The most common type of plastic found was polypropylene, followed by polyamide, nylon and polyethylene vinyl acetate. Polypropylene is often used in manufacturing furniture, clothing, rugs or packaging for cleaning products. Polyamide and nylon are similar microplastics and are both often used for textiles like clothing and carpets. Polyethylene vinyl acetate is used as a flexible plastic for manufacturing goods like adhesives, paints or plastic wrap.
Key Background
In recent years, microplastics have been traced from their disposal in the ocean and in landfills to human bodies. Microplastics are pieces of plastic less than 5 millimeters in length and are created from the breakdown of single-use bottles, food packages and plastic pellets, or plastics used to make packaging, auto parts, toys and other items. Studies have found that people can ingest microplastics directly, including through crops, fish and plastic food containers, which could leach microplastics into the food they hold. The European Union announced last year they would ban microplastics that are added to new products to help curb microplastic pollution. A similar effort to curb microplastic pollution in the U.S. was introduced in 2020, though it did not progress in the House.
Tangent
Microplastics have been found in human blood, hearts, the reproductive systems of men, lungs and liver tissues, mother’s milk and the placenta, among other organs. Other studies have linked microplastics to lung inflammation and a higher risk of lung cancer, metabolic disorders, neurotoxicity, endocrine disruption, weight gain, insulin resistance and decreased reproductive health. One study published earlier this year linked higher mortality rates to people with high levels of microplastics in their arteries.
Big Number
50,000. That’s how the estimated number of microplastics particles ingested by the average human every year, the Guardian reported. Other studies indicate the average human will ingest about 5 grams of plastic every week.
Further Reading
ForbesMicroplastics Have Been Found In Human Blood, Hearts, Testicles—Here’s How They Got ThereBy Mary Whitfill Roeloffs