Microplastics are now practically everywhere. We breathe them, we ingest them through water and food and, as numerous studies have shown in recent years, they can also reach our body.
One of the discoveries that had attracted the most attention had come from Italy. In 2024, a study conducted by the University of Campania “Luigi Vanvitelli” and published on New England Journal of Medicine had identified microplastics and nanoplastics in atherosclerotic plaques removed from the carotid arteries of some patients.
In that research, the presence of polyethylene and polyvinyl chloride in the plaques was associated with a higher risk of heart attack, stroke and death in the follow-up period. An important result, which however the authors themselves had invited to interpret with caution: it was in fact an association and not the demonstration of a cause-effect relationship.
Now, the same line of research is enriched with new data.
Microplastics in the blood of heart attack patients
The new study, published inEuropean Heart Journalwas created by researchers from the Sapienza University of Rome, the University of Verona and the “Luigi Vanvitelli” Research Center on Environmental Pollution and Cardiovascular Diseases of the University of Campania, directed by Giuseppe Paolisso together with Raffaele Marfella.
The research involved 61 patients undergoing coronary angiography. The researchers collected blood samples from both coronary arteries and peripheral vessels and analyzed them for microplastics and nanoplastics.
The most significant result concerns patients who had just had an acute myocardial infarction. Plastic particles were detected in 84% of them, a significantly higher percentage than that observed in patients with chronic ischemic heart disease (40%) and in people with normal coronary arteries (32%).
Not only that: significantly higher concentrations of micro- and nanoplastics in coronary blood were detected in heart attack patients, as well as a greater variety of polymers. Among those most frequently identified was polyethylene, one of the most widespread plastics, widely used for packaging and numerous everyday products.
The role of smoking and air pollution
The study also tried to understand which factors could be associated with a greater presence of these particles in the blood.
What emerges above all is the role of environmental exposure. Patients who lived in areas characterized by higher concentrations of PM2.5, the fine particulate matter capable of penetrating deep into the respiratory system, were more likely to have microplastics in their blood.
The most notable finding, however, concerns cigarette smoking. According to the research results, smokers were approximately six times more likely to have micro- and nanoplastics in their blood than non-smokers.
A possible explanation is that particles present in smoke and the environment can enter the body through the lungs and subsequently reach the bloodstream. According to the researchers, smoking, air pollution and microplastics could therefore together contribute to greater stress on the cardiovascular system.
Microplastics and inflammation
Another interesting element concerns inflammation. Higher levels of some inflammatory markers were also detected in patients with higher concentrations of microplastics, including TNF-α (tumor necrosis factor alpha) and IL-6 (interleukin-6).
These results suggest a possible relationship between the presence of plastic particles in the body and the inflammatory processes that can accompany acute cardiovascular events.
This is particularly important because inflammation has a well-known role in the development and progression of cardiovascular diseases. However, even in this case, the study does not yet allow us to establish with certainty what the direction of the relationship is: that is, we do not know whether microplastics directly contribute to inflammation and heart attack or whether their greater presence is linked to other factors associated with the patients’ conditions.
Do microplastics cause heart attacks?
This is the question that inevitably emerges when faced with results of this type. And the answer, at the moment, is no: we still don’t have proof that microplastics directly cause heart attacks.
The new study is in fact observational and involved a relatively small number of people. The data show a strong association between the presence of micro- and nanoplastics in the blood, exposure to certain environmental factors and the presence of an acute myocardial infarction, but cannot demonstrate a causal relationship.
For this reason too, broader and more in-depth research will be necessary, which will allow us to better understand how these particles enter the body, how long they remain in circulation and, above all, whether they can directly contribute to the biological mechanisms that lead to a cardiovascular event.
The new study is however important because it adds a piece to what had already emerged from the Italian research in 2024. At that time, microplastics had been found inside the atherosclerotic plaques of the carotid arteries and their presence had been associated with a greater risk of cardiovascular events. Now researchers have observed a greater presence of these particles in the blood of people suffering from acute heart attacks.
They are therefore two different observations but which go in the same direction and which reinforce the need to study more carefully the possible role of microplastics in cardiovascular health.
In the meantime, plastic continues to be an increasingly difficult presence to avoid: it is in the environment, in the air we breathe, in water and in food. Research is now trying to understand not only how much we are exposed, but also what consequences this exposure can have on our organism.
And as scientists continue to investigate, one thing becomes increasingly clear: reducing the dispersion and use of plastic is not only an environmental issue, but could also become an important part of preventing health risks.
