A cheap fermented vegetable and staple of Korean cuisine may help in combating a build-up of harmful microplastics linked to heart disease, cancer, inflammation and brain damage.
In a new study, a beneficial bacterium isolated from kimchi was found to bind to nanoplastics in the intestines and carry them out of the body.
Nanoplastics are tiny plastic particles even smaller than microplastics, measuring just one micrometer (µm) or less in diameter, making them invisible to the naked eye.
These particles have built up in the environment as well as the human body since the plastic boom of the last century, where their continued presence is increasingly linked to adverse health effects.
The bacterium, Leuconostoc mesenteroides, relied on a surface binding process that trapped nanoplastics before they infiltrated human tissue. In lab experiments, the bacterium trapped up to 87 percent of nanoplastics and 57 percent of them in gut-like conditions.
When tested in mice, those given the bacterium excreted significantly more plastic in their feces than untreated mice, which was evidence that it latched onto the particles and helped flush them out.
It comes as the world is inundated with plastic and its manufacturing byproducts, which have firmly implanted themselves in the environment and the water supply. Such particles have also been detected in human testicles, brains and gastrointestinal organs.
Depending on the brand, kimchi costs about $5 for a ten to 16oz jar or $15 for a bulk 35oz container (around $0.50 per ounce).
Researchers suggested that the food, which is rich in gut-healthy microbes, could provide a simple solution for reducing the negative impacts of nanoplastic exposure.
Nanoplastics have firmly embedded themselves in the environment -- and in drinking water, including bottled water. Studies have shown these particles can cross the blood-brain barrier, raising concerns about potential long-term neurological harm.
Dr Se Hee Lee, co-author and researcher at the World Institute of Kimchi in South Korea, said: 'Plastic pollution is increasingly recognized not only as an environmental issue but also as a public health concern.'
'Our findings suggest that microorganisms derived from traditional fermented foods could represent a new biological approach to address this emerging challenge.'
To find a bacterial solution to nanoplastics, researchers turned to kimchi and isolated Leuconostoc mesenteroides CBA3656, a lactic acid bacterium generally recognized as safe for human consumption.
While the study did not formally evaluate its probiotic properties, the strain is live, derived from food, and lacks genes that would make the bacterium harmful or disease-causing, meaning it could serve as a probiotic with the added benefit of binding nanoplastics in the gut.
In the lab, they exposed the bacteria to polystyrene nanoplastics -- particles just 190 nanometers wide, far smaller than a human cell -- under a wide range of conditions, varying everything from contact time and plastic concentration to pH, temperature and whether the bacteria were alive or heat-killed.
The plastics stuck to the outside of the bacteria rather than being taken into the cells, meaning the bacteria did not have to work to break them down.
To see if the strain could hold up in the human gut, the team tested it in simulated intestinal fluid containing bile salts, a notoriously harsh environment that can disrupt bacterial cell walls and render them ineffective at binding plastics.
Scientists reported in the journal Bioresource Technology that CBA3656 absorbed 57 percent of nanoplastics in intestinal fluid to mimic the human gut, outperforming other tested strains by as much as 19-fold.
When mixed together, both bacterial strains CBA3608 and CBA3656 became covered in clinging plastic particles -- visible as white specks coating the cells. The outside-only binding suggests the bacteria could safely carry plastics through the gut without internal disruption, supporting their potential use as a living escort system for nanoplastics.
Researchers also placed CBA3656 in sterile water with nanoplastics and tested different concentrations of bacteria. At 500 million bacteria per milliliter, the strain trapped 87 percent of the plastics, its peak performance under ideal conditions.
Then, they moved from the petri dish to a living system.
In a germ-free mouse model, chosen to eliminate interference from existing gut microbes, mice were orally administered the bacterium before receiving a dose of nanoplastics.
Those that had received CBA3656 excreted significantly higher levels of plastics in their feces than the control group, providing direct evidence that the bacterium could bind nanoplastics in a live intestine and help flush them out of the body.
The researchers said: 'Collectively, this work not only highlights microbial biosorption as a promising and practical approach to address NP contamination but also provides new insights into microbe-based strategies for NP removal in environmental and health contexts.'
The study had some notable limitations. The study provides strong proof-of-concept evidence in controlled settings, but real-world applicability, long-term safety and actual health benefits remain to be demonstrated.
All experiments were conducted under controlled laboratory conditions. Natural ecosystems are far more complex and variable.
The live-animal portion of the study used germ-free mice to eliminate microbial interference. While this allowed clean measurement of the strain's effects, it does not capture the complexity of a normal gut with its native microbiota.
Depending on the brand, kimchi costs about $5 for a ten to 16oz jar or $15 for a bulk 35oz container (around $0.50 per ounce).
When tested in simulated intestinal fluid, a laboratory proxy for the human gut complete with bile salts, Leuconostoc mesenteroides CBA3656 adsorbed an impressive 57 percent of nanoplastics, far outpacing the others. The next closest strain managed only about 18 percent.
The study also only measured acute exposure over a short period. But every American has been exposed to nanoplastics since childhood, leading to chronic exposure and ample time for the sinister particles to lodge in human tissues.
And researchers only measured how much nanoplastics were excreted. They did not measure absorption in organs after the strain was given, so there was no way to know whether the bacterium helped clear the particles already in tissues or had anti-inflammatory benefits.
Nanoplastics are ingested via contaminated seafood, drinking water and salt. Sunlight, friction, heat, and time keep breaking larger debris apart, which steadily increases the number of particles people can swallow.
People do not need to eat plastic directly because tiny fragments also show up in the air. It is nearly impossible to avoid them.
Studies have pointed to nanoplastics' adeptness at entering the brain more readily than kidneys and other organs, indicating that their small size and ability to interact with fatty tissues allow them to cross the blood-brain barrier.
An expanding body of scientific research has linked nanoplastics in the brain to cause a range of pathological changes, including inflammation, oxidative stress, an accumulation of Alzheimer's-associated amyloid plaques, as well as Parkinson's-linked Alpha-synuclein proteins.
Research has linked nanoplastics to cancer, though the International Agency for Research on Cancer (IARC) has not yet classified them as carcinogens.
A study from February 2026 found that prolonged, low-level exposure to tiny plastic particles -- just 20 nanometers wide -- made colorectal cancer cells behave more aggressively.
The plastics seemed to give cancer cells a survival boost, making them more likely to spread and migrate to new sites. When researchers tested the same particles in zebrafish, they watched the cancer spread faster in real time.