Mind-bending material aka microplastics
Microplastics—tiny plastic particles less than 5 mm in size, including nano-plastics at less than 0.001mm—are increasingly infiltrating ecosystems and living organisms, including humans. These particles originate from the breakdown of larger plastics and are now found in food, air, and water. Scientists have discovered that microplastics can penetrate animal brains, altering behaviour and cognitive functions. In hermit crabs, for instance, exposure impairs their ability to choose suitable shells, while fish struggle with navigation, shrimp become hyperactive, and honeybees suffer memory loss. These behavioural changes suggest neurotoxicity and potential bioaccumulation in the central nervous systems of various species.
Alarmingly, microplastics have also been detected in human brain tissue, raising concerns about their neurological impact. Animal studies show that microplastics can breach the blood-brain barrier, causing inflammation, neuron death, and symptoms resembling dementia. Even without entering the brain, microplastics can disrupt gut microbiota, which affects gut-brain communication. In mice, this has led to antisocial behaviour and potential reproductive issues.
Human vulnerability may be greater due to constant exposure to plastics in daily life. Early research on brains donated to science from people diagnosed with dementia has shown that their brains appear to have more microplastics present than others.
Experts recommend reducing exposure by avoiding plastic packaging, choosing organic foods, consuming probiotics to strengthen the blood-brain barrier, and eating leafy greens rich in vitamin E to combat inflammation.
While the full extent of microplastics’ impact on human health remains uncertain, the evidence from animal studies and early human data is troubling. The pervasive presence of microplastics in our environment and bodies underscores the urgent need for further research and preventive measures. The potential long-term consequences for mental health and ecological stability are increasingly concerning, making microplastic pollution a critical issue for both environmental and public health.
Summarised by Mike Tester from an article in New Scientist dated 10 May 2025 by Marta Zaraska