Microplastics have infiltrated our environment, our food, and even our bodies. As concerns over their potential health effects grow, a new study highlights a troubling discovery: these tiny plastic fragments may disrupt blood flow in the brain, leading to cognitive impairments.
Researchers from the Chinese Research Academy of Environmental Sciences in Beijing conducted an experiment tracking microplastic movement in the blood vessels of live mice—marking the first time this has been done in real-time. Their findings suggest that microplastics can cause dangerous blockages in the brain’s blood supply, raising concerns about their long-term effects on neurological health.
Microplastics in the Brain: A Hidden Threat
Using advanced high-resolution laser imaging, the researchers observed microplastic-laden immune cells becoming lodged inside blood vessels in the cortex region of the brain. Rather than directly penetrating brain tissue, the microplastics appeared to disrupt circulation by blocking tiny blood vessels, similar to how blood clots form.
“Our data reveal a mechanism by which microplastics disrupt tissue function indirectly through regulation of cell obstruction and interference with local blood circulation, rather than direct tissue penetration,” the researchers wrote in their published paper in Science Advances (2025).
Cognitive and Behavioral Impacts
To assess the impact of these blockages, the team monitored the behavior of mice exposed to microplastics. Their results showed that mice with plastic-contaminated blood performed worse in memory, coordination, and movement tests compared to those without microplastic exposure. This suggests that reduced blood flow in the brain may lead to temporary cognitive impairment.
Microplastics are defined as plastic fragments smaller than 5 millimeters (0.2 inches) in diameter. The study found that larger microplastic particles were more likely to cause obstructions than smaller ones.
While the blockages eventually cleared within a month, and most cognitive functions returned to normal, researchers caution that prolonged exposure could have long-term effects, potentially increasing the risk of neurological disorders, depression, anxiety, strokes, and cardiovascular disease.
“These findings indicate that mice display multifaceted abnormalities in neurobehavioral regulation, resembling depressive states associated with disrupted cerebral blood flow,” the researchers added.
Implications for Human Health
While the study provides valuable insights, it’s still unclear whether these same effects occur in human brains. Differences in immune system function and blood vessel structure mean that further research is needed.
Mice, however, share biological similarities with humans, making these findings a cause for concern. The researchers emphasize that future studies should involve larger mammals or animal models with circulatory systems closer to humans, such as primates, to determine the full extent of the risks.
As microplastics continue to accumulate in the environment, understanding their potential impact on human health is becoming increasingly urgent. Scientists are now exploring possible links between microplastics and diseases, but no direct connection in humans has yet been confirmed.
For now, this study underscores the importance of reducing plastic pollution and finding ways to limit microplastic exposure in our daily lives.