Microplastics found in human arteries double the risk of heart attack and stroke

The micros and the nanoplastics they are now widely spread, not only in the surrounding environment but also within our body. These contaminants have been detected in various organs and tissues, including the placenta, breast milk, liver, lungs and even heart tissues. But recently, a study conducted in Italy revealed the presence of micro and nanoplastics inside the atherosclerotic plaquesor in the accumulations of fat in the coronary arteries.

The Italian team

The results of this study, published in the New England Journal of Medicine, indicate that contaminated atherosclerotic plaques are more inflamed than normal, making them more vulnerable to rupture. This translates into a risk of heart attack, stroke and mortality at least two times higher compared to atherosclerotic plaques not contaminated by plastic.

The study is the result of a broad collaboration, led by researchers atUniversity of Campania Luigi Vanvitelli, which involves numerous research institutions, including the Harvard Medical School of Boston, the IRCSS Multimedica of Milan and the universities of Ancona, Sapienza of Rome and Salerno, together with the IRCSS INRCA of Ancona. This collaboration highlighted that atherosclerotic plaques often contain micro- and nanoplastics derived from polyethylene (PE) or polyvinyl chloride (PVC), two of the most widespread plastic compounds in the world, used for a vast range of products ranging from containers to coatings, from plasticized films to building materials.

The results of the study

The study was conducted on 257 patients over the age of 65 who underwent endarterectomy for asymptomatic carotid stenosis. During this surgical procedure, atherosclerotic plaques were removed and analyzed under an electron microscope to identify the presence of micro- and nanoplastics, i.e. plastic particles with a diameter of less than 5 millimeters or 1 micron (0.001 millimetres), respectively.

According to Giuseppe Paolisso, coordinator of the study and professor of Internal Medicine at the University of Campania “Luigi Vanvitelli”, the analysis revealed the presence of polyethylene particles in measurable levels (about 20 micrograms per milligram of plaque) in 58.4% of patients and polyvinyl chloride particles, averaging 5 micrograms per milligram of plaque, in 12.5%. Microplastics are now found everywhere, even in our bodies.

Furthermore, all participants were followed for approximately 34 months, during which it was observed that those who presented plaques “contaminated” by plastics had a risk of heart attack, stroke or mortality for all causes at least doubled compared to those who did not have atherosclerotic plaques containing micro- and nanoplastics, regardless of other cardio-cerebrovascular risk factors. Significant increases in inflammatory markers were then observed locally in the presence of micro- and nanoplastics. It is not the first time that microplastics have been found in the body, given that a recent study had also identified them in the lungs.

How plastics affect the body

In the study, the researchers also illustrated the mechanism behind heart damage caused by plastic. Raffaele Marfella, creator of the study and professor of Internal Medicine at the University of Campania “Luigi Vanvitelli”, explains that the pro-inflammatory effect could be one of the reasons why the micro and nanoplastics increase the instability of plaquesincreasing the risk of rupture and consequently thrombosis, which can lead to heart attacks or strokes.

Marfella continues by explaining that data collected both in vitro and in experimental animals have already highlighted that micro- and nanoplastics can promote oxidative stress and inflammation in vascular endothelial cells. She also adds that these particles can alter the heart rhythm and contribute to the development of fibrosis and cardiac dysfunction. These results, according to Marfella, represent the first evidence of a direct correlation between the presence of micro- and nanoplastics and an increased risk of cardiovascular disease in humans.