In a recent study published in the journal Science Advances, researchers investigated the impact of microplastics on blood flow and neurobehavioral functions in mice. Using advanced imaging techniques, they observed that microplastics obstruct cerebral blood vessels by causing individual immune cells to become trapped in capillaries. The findings revealed a novel mechanism through which microplastics indirectly disrupt vascular and neurological functions without crossing the blood-brain barrier.
Microplastics and human health
Microplastics originate from plastic degradation and are being recognized as environmental pollutants with potential health risks to humans and ecosystems. These particles can enter the human body through ingestion, inhalation, or medical devices. Research shows that microplastics can cross biological barriers, such as the blood-brain barrier, and interact with various physiological systems, including the immune and cardiovascular systems.
While nanoscale plastics have been linked to neurological disorders (e.g., exacerbating α-synuclein pathology associated with Parkinson’s disease) and inflammation, the impact of micron-sized microplastics remains unclear. Previous studies have demonstrated that microplastics can induce immune responses, alter cellular functions, and affect blood perfusion, potentially leading to organ dysfunction. However, the specific mechanisms of microplastic-induced vascular or neurological disruptions, particularly in vivo, are poorly understood.
About the study
The present study employed various in vivo and ex vivo methods to investigate how microplastics affect blood flow and neurobehavioral functions in mice. Eight-week-old male mice were housed under controlled conditions and used as the study model. The researchers intravenously injected fluorescently labeled polystyrene microplastics of three sizes — 5 µm (micron-sized), 2 µm, and 80 nm (nanoscale) — into mice at concentrations designed to mimic human exposure levels.
The study used advanced imaging techniques, including laser speckle contrast imaging and miniature two-photon microscopy, to visualize the microplastics within cerebral blood vessels. These methods provided high-resolution, real-time tracking of microplastic movements and vascular interactions.
Blood samples were also collected for flow cytometry analysis to identify the immune cells responsible for microplastic uptake and obstruction. Specifically, the cells labeled with fluorescent microplastics were sorted and characterized to understand the role of immune cells, such as neutrophils and macrophages, in the phagocytosis of microplastics. Phagocytosis altered immune cell morphology, increasing their size (forward scatter) and reducing granularity (side scatter), which contributed to vascular blockages.
Additionally, behavioral experiments, including open-field, Y-maze, rotarod, and rod-hanging tests, were conducted to evaluate the neurobehavioral effects of microplastics in mice. These tests assessed exploratory behavior, memory, motor coordination, and endurance after microplastic exposure.
Laser speckle imaging was also performed to measure cerebral blood perfusion at various time points post-injection to determine how microplastics affected vascular flow. The combination of imaging, behavioral, and cellular analyses provided a comprehensive understanding of how microplastics interact with the vascular and neurological systems.
Key findings
The study found that microplastics disrupt vascular and neurobehavioral functions by causing immune cells that ingested them to become mechanically trapped in narrow cerebral vessels. The researchers observed individual immune cells (termed MPL-Cells) laden with microplastics obstructing blood flow, particularly in capillaries.
These obstructions reduced cerebral blood perfusion within 30 minutes, with the most significant effects in smaller vessels. Unlike classical blood clots, these blockages stemmed from physical cell entrapment rather than platelet activation or clotting cascades.
The behavioral experiments demonstrated that mice exposed to microplastics exhibited decreased locomotion, impaired memory, and reduced motor coordination. Open-field and Y-maze tests showed significant reductions in movement speed and spatial memory, while rotarod and rod-hanging tests indicated decreased motor skills and endurance. Although neurobehavioral impairments resolved within four weeks, some vascular obstructions persisted at lower densities.
Further analysis indicated that larger microplastics (5 µm) caused prolonged obstructions, while smaller particles (2 µm and 80 nm) were cleared faster. The results from flow cytometry revealed that phagocytosis of microplastics altered immune cells’ morphology and adhesive properties, contributing to vascular blockages. These findings suggested that microplastics’ size, concentration, and interactions with immune cells are critical factors in their impact on vascular and neurological health.
The study emphasized the potential health risks of microplastics, particularly their ability to obstruct blood vessels and disrupt brain function. However, the authors cautioned that translating these findings to humans requires further research due to differences in vascular size and physiology between mice and humans.
Conclusions
To summarize, the findings revealed the mechanisms through which microplastics obstruct blood flow and impair neurobehavioral functions via immune cell entrapment in cerebral vessels. Factors such as particle size were also found to influence these effects, with smaller microplastics causing less obstruction.
While the neurobehavioral impairments due to microplastics in mice were largely reversible, residual vascular obstructions persisted even after behavioral recovery. The findings emphasized the need for further research on the long-term health risks posed by microplastics, particularly in individuals with pre-existing cardiovascular conditions or narrowed blood vessels.
- Huang, H., Hou, J., Li, M., Wei, F., Liao, Y., & Xi, B. (2025). Microplastics in the bloodstream can induce cerebral thrombosis by causing cell obstruction and lead to neurobehavioral abnormalities. Science Advances, 11(4), eadr8243. DOI: 10.1126/sciadv.adr8243, https://www.science.org/doi/10.1126/sciadv.adr8243

News
Studies detail high rates of long COVID among healthcare, dental workers
Researchers have estimated approximately 8% of Americas have ever experienced long COVID, or lasting symptoms, following an acute COVID-19 infection. Now two recent international studies suggest that the percentage is much higher among healthcare workers [...]
Melting Arctic Ice May Unleash Ancient Deadly Diseases, Scientists Warn
Melting Arctic ice increases human and animal interactions, raising the risk of infectious disease spread. Researchers urge early intervention and surveillance. Climate change is opening new pathways for the spread of infectious diseases such [...]
Scientists May Have Found a Secret Weapon To Stop Pancreatic Cancer Before It Starts
Researchers at Cold Spring Harbor Laboratory have found that blocking the FGFR2 and EGFR genes can stop early-stage pancreatic cancer from progressing, offering a promising path toward prevention. Pancreatic cancer is expected to become [...]
Breakthrough Drug Restores Vision: Researchers Successfully Reverse Retinal Damage
Blocking the PROX1 protein allowed KAIST researchers to regenerate damaged retinas and restore vision in mice. Vision is one of the most important human senses, yet more than 300 million people around the world are at [...]
Differentiating cancerous and healthy cells through motion analysis
Researchers from Tokyo Metropolitan University have found that the motion of unlabeled cells can be used to tell whether they are cancerous or healthy. They observed malignant fibrosarcoma cells and [...]
This Tiny Cellular Gate Could Be the Key to Curing Cancer – And Regrowing Hair
After more than five decades of mystery, scientists have finally unveiled the detailed structure and function of a long-theorized molecular machine in our mitochondria — the mitochondrial pyruvate carrier. This microscopic gatekeeper controls how [...]
Unlocking Vision’s Secrets: Researchers Reveal 3D Structure of Key Eye Protein
Researchers have uncovered the 3D structure of RBP3, a key protein in vision, revealing how it transports retinoids and fatty acids and how its dysfunction may lead to retinal diseases. Proteins play a critical [...]
5 Key Facts About Nanoplastics and How They Affect the Human Body
Nanoplastics are typically defined as plastic particles smaller than 1000 nanometers. These particles are increasingly being detected in human tissues: they can bypass biological barriers, accumulate in organs, and may influence health in ways [...]
Measles Is Back: Doctors Warn of Dangerous Surge Across the U.S.
Parents are encouraged to contact their pediatrician if their child has been exposed to measles or is showing symptoms. Pediatric infectious disease experts are emphasizing the critical importance of measles vaccination, as the highly [...]
AI at the Speed of Light: How Silicon Photonics Are Reinventing Hardware
A cutting-edge AI acceleration platform powered by light rather than electricity could revolutionize how AI is trained and deployed. Using photonic integrated circuits made from advanced III-V semiconductors, researchers have developed a system that vastly [...]
A Grain of Brain, 523 Million Synapses, Most Complicated Neuroscience Experiment Ever Attempted
A team of over 150 scientists has achieved what once seemed impossible: a complete wiring and activity map of a tiny section of a mammalian brain. This feat, part of the MICrONS Project, rivals [...]
The Secret “Radar” Bacteria Use To Outsmart Their Enemies
A chemical radar allows bacteria to sense and eliminate predators. Investigating how microorganisms communicate deepens our understanding of the complex ecological interactions that shape our environment is an area of key focus for the [...]
Psychologists explore ethical issues associated with human-AI relationships
It's becoming increasingly commonplace for people to develop intimate, long-term relationships with artificial intelligence (AI) technologies. At their extreme, people have "married" their AI companions in non-legally binding ceremonies, and at least two people [...]
When You Lose Weight, Where Does It Actually Go?
Most health professionals lack a clear understanding of how body fat is lost, often subscribing to misconceptions like fat converting to energy or muscle. The truth is, fat is actually broken down into carbon [...]
How Everyday Plastics Quietly Turn Into DNA-Damaging Nanoparticles
The same unique structure that makes plastic so versatile also makes it susceptible to breaking down into harmful micro- and nanoscale particles. The world is saturated with trillions of microscopic and nanoscopic plastic particles, some smaller [...]
AI Outperforms Physicians in Real-World Urgent Care Decisions, Study Finds
The study, conducted at the virtual urgent care clinic Cedars-Sinai Connect in LA, compared recommendations given in about 500 visits of adult patients with relatively common symptoms – respiratory, urinary, eye, vaginal and dental. [...]