There has been a lot of talk about pollution these days, a phenomenon that is also bad for the heart. But how? An Italian study, the first to have identified the presence of microplastics directly in human arteries, highlights a previously underestimated aspect.

After finding them in humans in several organs and tissues, including the placenta, breast milk, liver and lungs, including heart tissues, researchers have now discovered microplastics in atherosclerotic plaques, fatty deposits in the arteries that are dangerous for the heart. .
Researchers from the University of Campania Luigi Vanvitelli monitored 257 patients over 65 for 34 months after an operation to remove the atherosclerotic plaques that occlude the carotid arteries, observed under an electron microscope in search of microplastics. And here came the ‘surprise’: the team detected measurable quantities of polyethylene (PE) in 58.4% of cases and polyvinyl chloride (PVC) in 12.5%. These are compounds used to make, among other things, containers, coatings, plasticized films and building materials.

In these patients the risk of cardiovascular events such as heart attack, stroke and mortality from all causes was up to 2 times higher than in those who had not accumulated microplastics inside the plaques. Not only that, these substances are also associated with greater local inflammation which makes the ‘pollution’ plaques more unstable and crumbly.

“All the participants were followed for approximately 34 months – underlines Giuseppe Paolisso, coordinator of the study and Professor of Internal Medicine at the Vanvitelli University (in the photo below) – and it was observed that in those who had plaques ‘polluted’ by plastics the risk of heart attacks, strokes or mortality from all causes was at least doubled compared to those without atherosclerotic plaques containing micro- and nanoplastics, regardless of other cardio-cerebrovascular risk factors such as age, sex, smoking, body mass index, cholesterol values, blood pressure and blood sugar or previous cardiovascular events. The data also shows a significant local increase in inflammatory markers in the presence of microplastics.”

“The pro-inflammatory effect could be one of the reasons why microplastics lead to greater instability of the plaques and therefore a greater risk of them breaking, giving rise to thrombi and thus causing heart attacks or strokes – explains Raffaele Marfella, creator of the study and Professor of Internal Medicine of the Vanvitelli University – Data collected in vitro and in experimental animals have already shown that “these substances” can promote oxidative stress and inflammation in the cells of the endothelium covering the blood vessels, but also alter the rhythm cardiac and contribute to the development of fibrosis and alterations in the functionality of the heart: these results show for the first time in humans a correlation between the presence of micro- and nanoplastics and a greater cardiovascular risk”.

“Our study did not investigate the origin of the micro and nanoplastics detected in the plaques: considering the widespread diffusion of PE and PVC, attributing their source to humans is almost impossible – points out Antonio Ceriello of the Irccs Multimedica in Milan – Although our data do not establish a cause-effect relationship, however they suggest that micro- and nanoplastics could constitute a new, important cardiovascular risk factor to take into account.”

According to the latest Future Brief report on nanoplastics from the European Commission, on average an adult inhales or ingests 39,000 to 52,000 plastic particles per year, 5 grams of plastic per week. The equivalent, all things considered, of a credit card.

The Italian study, published in the ‘New England Journal of Medicine’, is accompanied by an editorial of the journal which defines the research as “a revolutionary discovery that raises a series of urgent questions: exposure to microplastics and nanoplastics can be considered a new factor of cardiovascular risk? What organs other than the heart may be at risk? How can we reduce exposure?”.

“The first step – writes the epidemiologist Philip J. Landrigan, founder and director of the Global Public Health Program of Boston College and of the Global Pollution Observatory within the Schiller Institute for Integrated Science and Society, who signs the editorial – is to recognize that the low cost and convenience of plastic are deceptive and which, in fact, hide great damage, such as the contribution of plastic to the outcomes associated with atherosclerotic plaque”.

“We must encourage our patients to reduce their use of plastic, especially unnecessary single-use items, and support the United Nations Global Plastics Treaty to mandate a global cap on plastic production. As with climate change – warns the epidemiologist – solving the problems associated with plastic will also require a large-scale transition away from fossil carbon”.