Microplastics in human organs: what are the health implications?

Where do microplastics accumulate? 

The most significant finding of the study is the accumulation of microplastics in post-mortem samples of human brains. This finding provides the first human evidence that microplastics can cross the blood-brain barrier—a protective layer against toxic substances. Until now, this phenomenon had only been observed in animal models. The implications are concerning: breaching this biological defence could pose serious risks to brain health. 

In addition, the study found accumulation of microplastics in the liver and kidneys—organs primarily responsible for filtering and eliminating toxins from the body. Thus, this finding suggests that our body may not have sufficient capacity to eliminate these particles and they may persist and/or accumulate over time. 

Implications for vascular health and stroke risk 

Another recent study, published in the New England Journal of Medicine detected microplastics in atherosclerotic plaques in patients undergoing surgery on their carotid arteries—the main arteries supplying blood to the brain. 

Once inside the body, microplastics can trigger inflammatory responses and alter our metabolism, increasing the presence of oxidative agents. This inflammation and oxidative processes can damage blood vessels, impair brain vascular health, and may raise the risk of stroke. This emerging risk adds to well-established stroke risk factors such as high cholesterol, diabetes, hypertension, smoking, and excessive alcohol use.  

The difficulty of detecting microplastics in patients: a public health challenge 

One of the biggest challenges in how to study and detect these microplastics lies in their minuscule size. Currently, one of the key public health challenges is to develop new methods for detecting microplastics in circulation, not just in tissue samples from deceased individuals, in order to better understand how these particles travel through the body and the potential risks they pose to human health.  

Individual preventive measures 

It is recommended to adopt simple everyday actions to help reduce exposure to microplastics and minimise direct contact as much as possible: 

• Avoid plastic-packaged foods. 
• Drink less bottled water (opt for filtered water instead). 
• Avoid heating food in plastic containers, as heat can break down the plastic and release particles. 
• Ventilate indoor spaces regularly and avoid products that contain microbeads (e.g. cosmetics). 

Recent researches reveal that microplastics accumulate in vital human organs and may contribute to the development of neurological and vascular diseases, such as stroke. Their ability to cross biological barriers, combined with the difficulty of eliminating them and detecting them in living individuals, represents an emerging challenge for public health. In light of this situation, it is essential to promote preventive actions at the individual level and to develop diagnostic tools that can help us better understand how microplastics affect the human body. 

INFORMATION DOCUMENTED BY:  

Dr. Arturo Renú, neurologist. Hospital Clínic Barcelona.