Microplastics are particles ranging from 1 micrometer to 5 millimeters in diameter, and nanoplastics, which are even smaller, are found in virtually every environment on Earth, from mountain peaks to ocean depths, and from the smallest animals in the food chain to human brain cells.
These particles can originate from the breakdown of larger plastic items or be intentionally manufactured for use in products, such as cosmetics, synthetic fabrics, and pharmaceuticals. Recent studies suggest that the human brain may contain up to a teaspoon of microplastics and nanoplastics, with the tiniest fragments primarily composed of polyethylene, the same material commonly used in plastic bags and food packaging.
These particles have been detected in areas such as the walls of blood vessels in the brain and within immune cells. However, it remains unclear whether microplastics contribute to the progression of neurological diseases or whether these conditions render the brain more susceptible to particle infiltration. In animal studies involving fish and rodents, prolonged exposure to nanoplastics has been linked to memory impairment, brain inflammation, and alterations in synaptic protein levels.
Beyond the brain, microplastics have been found in human feces, arterial plaques, and even the placenta. A study published in The New England Journal of Medicine linked the presence of microplastics in the arteries to a heightened risk for heart attack, stroke, and overall mortality.
Therapeutic Apheresis
According to a preliminary study published in Brain Medicine by researchers at Technische Universität Dresden in Dresden, Germany, therapeutic apheresis, a medical procedure that filters tiny particles from the blood, may help remove microplastics from the human body. The technique can capture particles as small as 200 nanometers, which is approximately 5000 times smaller than a millimeter.
In this study, the researchers evaluated the procedure in patients with myalgic encephalomyelitis, also known as chronic fatigue syndrome. They analyzed the waste fluid discarded during apheresis using a specialized infrared spectroscopy technique.
The analysis detected substances that matched the chemical signatures of polyamide and polyurethane, two common types of industrial plastics. This suggests that microplastics may have been successfully removed from the blood of patients during the procedure.
Notably, this study did not measure the total amount of microplastics removed or compare their levels in patients before and after apheresis. What has been demonstrated so far is the presence of microplastics in the waste material discarded by the device — an observation that suggests, but does not yet confirm, the effective removal of these substances from the human body.
Researchers have cautioned that the detected materials may reflect chemical structures common to proteins, meaning that further analysis is required to verify the exact nature of the removed particles. Nonetheless, the findings offer hope to researchers seeking to address the growing accumulation of microplastics in the human body.
The authors recommended conducting studies with larger groups and quantitative analyses comparing the levels of microplastics in the blood before and after the procedures. The authors concluded that “such analyses will help determine particle removal from blood and tissues and assess correlations with symptom improvement in conditions like myalgia encephalomyelitis/chronic fatigue syndrome.”
Alternative Approaches
Currently, evidence that microplastics are effectively removed from the human body after ingestion is limited.
A 2011 study examined bisphenol A (BPA) levels in blood, sweat, and urine samples from 20 individuals. In 16 cases, BPA appeared only in sweat, suggesting that induced perspiration may help eliminate certain compounds from the body. However, more studies are needed to assess its long-term safety and efficacy.
“That is why we focus on reducing exposure to microplastics in the first place,” said Nicholas Fabiano, MD, a psychiatry resident at the University of Ottawa, Ottawa, Ontario, Canada, and co-author of a related article in Brain Medicine.
The challenge of this research began with tracking the effects of microplastic particles. “From a clinical perspective, it is very difficult to establish a direct link between exposure to microplastics and adverse health outcomes,” said Fabiano.
To address this, he advocated the creation of new tools to measure dietary risks, such as a dietary microplastic index. “We propose the development of a Dietary Microplastic Index that could be integrated with existing dietary risk assessment tools to estimate microplastic exposure based on the types of food consumed,” he said.
This story was translated from Medscape’s Portuguese edition.