In recent decades, with the widespread use of plastic products, microplastics have become ubiquitous in the environment. More importantly, increasing research shows that these microplastics can accumulate in the human body; scientists have found them in the blood, lungs, kidneys, liver, reproductive system, and even the brain.
In real life, microplastics are everywhere. The air we breathe, bottled water, food packaging bags, takeout containers, etc., inevitably lead to our exposure to and ingestion of microplastics, which can potentially harm multiple organs and systems in the human body. Previous research has generally focused on detecting the presence of microplastics, revealing their potential toxic effects, and removing microplastics from the environment. For microplastics that have already invaded the human body, there is still no effective strategy for elimination.
Recently, two new studies by Chinese scholars have brought a new breakthrough in microplastic elimination-using newly discovered probiotics to adsorb and promote the elimination of microplastics from the body, while simultaneously repairing the damage caused by microplastics.
On January 10, 2025, a research team led by Dr. Rao Chitong, Chief Scientist of Blue Crystal Microbiology, published a research paper entitled "Novel probiotics adsorbing and excreting microplastics in vivo show potential gut health benefits" in the journal Frontiers in Microbiology.
Microplastic pollution from food and water poses a significant risk to biological health. Microorganisms have the potential to remove microplastics from the environment, but currently there is no method to remove these non-degradable microplastics already present in the human body. In this new study, the research team proposed using probiotics to adsorb and remove ingested microplastic particles in the gut.
The research team used a high-throughput screening method to comprehensively evaluate 784 bacterial strains to determine their ability to adsorb 0.1-micron-sized polystyrene (PS, commonly used in appliances, toys, daily necessities, plastic packaging, building materials, and medical devices). Among these strains, the research team discovered that two probiotics-Lactobacillus paracasei DT66 and Lactobacillus plantarum DT88-exhibited the best microplastic particle adsorption effect in vivo, and were effective against various types of microplastics (PS, PE, PC, PP, and PET).
Scanning electron microscopy showed that probiotics DT66 and DT88 could adsorb microplastics
Next, the research team conducted in vivo animal experiments. After mice were orally administered these probiotics, the probiotics were able to adsorb microplastics like magnets, forming "bacterial-plastic clumps," which were then excreted from the body. Specifically, the excretion rate of microplastics in the digestive system of the mice increased by 36%, and the amount of residual microplastic particles in the intestines decreased by 67%.
Furthermore, this study also confirmed that the Lactobacillus plantarum DT88 strain can alleviate intestinal inflammation caused by polystyrene (PS) microplastics. In summary, this study proposes a novel probiotic strategy for addressing microplastic-related health risks, highlighting the potential of using specific strains of probiotics to eliminate microplastics from the gut environment and reduce these risks.
Probiotics DT66 and DT88 promote microplastic elimination
On February 1, 2025, the team led by Rao Chitong from Lanjing Microbiology, in collaboration with the team led by Wang Gang from Jiangnan University, published a research paper in the journal *Environmental Pollution* entitled: "Lactic acid bacteria reduce polystyrene micro- and nanoplastics-induced toxicity through their bio-binding capacity and gut environment repair ability."
Microplastics are a newly emerging environmental pollutant that has received considerable attention in recent years. Currently, there is considerable research on the toxic effects of microplastics on animals (especially aquatic organisms and mammals), but research and data on reducing the toxic effects of exposure remain very limited.
Lactic acid bacteria (LAB, including Lactobacillus) are recognized as safe food-grade probiotics. They possess the ability to repair the intestinal barrier, regulate the gut microbiota, and modulate host immunity. They also have the ability to biobind harmful substances, potentially adsorbing microplastics in the human body and reducing their accumulation levels, thereby mitigating potential toxicity.
In this new study, the research team selected lactic acid bacteria (DT11, DT22, DT33, DT55, and DT66) with different in vitro microplastic binding capacities to intervene in mice exposed to microplastics, exploring their effectiveness in reducing the toxicity caused by microplastic exposure.
The results showed that lactic acid bacteria with higher microplastic adsorption capacity (DT11, DT33, DT55, and DT66, with adsorption rates exceeding 60%) were more effective in alleviating the toxicity caused by microplastic exposure. However, it is noteworthy that *Lactobacillus plantarum* DT22, despite exhibiting low microplastic adsorption (approximately 10%), played a crucial role in upregulating the expression levels of tight junction proteins (e.g., ZO-1) and regulating the gut microbiota.
Lactobacillus strains exhibiting microplastic adsorption, both in vivo and in vitro, effectively reduced the toxicity (e.g., hepatotoxicity and testicular toxicity) caused by microplastic exposure. This effect is achieved through two possible mechanisms: first, lactobacillus can adsorb microplastics and promote their excretion in feces, thereby reducing their accumulation in vivo; second, lactobacillus can repair the intestinal barrier, regulate the gut microbiota, and increase the production of short-chain fatty acids (e.g., butyrate).
Lactobacillus reduces microplastic-induced liver damage
Lactobacillus reduces microplastic-induced testicular and colonic damage
These results indicate that the mitigating effect of lactobacillus on microplastic toxicity lies not only in its bio binding capacity but also in its ability to repair the damaged intestinal environment. In other words, lactobacillus is not only a "carrier" in the gut (promoting microplastic excretion) but also a "repairman" (repairing microplastic-induced damage). Therefore, the research team recommends using probiotic lactic acid bacteria as a dietary intervention to reduce the toxicity caused by microplastics. Overall, these two innovative findings offer a completely new approach to addressing the microplastic problem and open new avenues for improving gut health and restoring gut microbiome balance, thus possessing significant environmental and health implications.
