Microplastics Impact Brain Function and Blood Circulation

Recent studies have revealed alarming vital information about the effects of microplastics on brain function. Research published in *Science Advances* indicates that microplastics may obstruct blood circulation, leading to impaired cognitive abilities. These findings stem from experiments conducted on mice, denoting the urgent need to understand the implications for human health.

What Are Microplastics?

Microplastics are plastic particles smaller than 5 millimetres.

They originate from the degradation of larger plastic items and from manufactured plastic pellets.

These particles are ubiquitous, found in oceans, soil, and even in remote regions like Antarctic ice.

Microplastics can enter the human body through various pathways, including ingestion and inhalation.

Mechanisms of Impact on the Brain

The study used advanced imaging techniques to observe microplastics in the mouse brain. Researchers tracked the movement of these particles in real-time. They found microplastics lodged in the blood vessels of the cerebral cortex, which is crucial for cognitive functions. Immune cells were seen engulfing the microplastics, causing blood vessel obstruction and impairing blood flow.

Effects on Cognitive Function

The obstruction of blood vessels resulted in cognitive impairments in the test subjects. Mice exhibited neurobehavioural abnormalities resembling depressive states. Weight loss was also noted, likely due to altered movement patterns affecting feeding behaviour. These findings suggest a direct link between microplastic exposure and neurological health.

Routes of Brain Interaction

Previous research identified two main routes through which microplastics may affect brain function.

The first is through peripheral organs, indirectly influencing neural activity.

The second route involves crossing the blood-brain barrier, which protects the brain from harmful substances.

The current study proposes a third mechanism involving direct obstruction of blood flow.

Implications for Human Health

While the study provides critical insights, researchers caution against directly extrapolating findings from mice to humans. Differences in immune systems, blood volume, and vascular structures can alter outcomes. For instance, the internal diameter of human coronary arteries is about 4 mm, compared to much smaller diameters in mice. Thus, the potential for microplastics to cause similar obstructions in humans remains uncertain.