In recent years, it has been seen that nanoplastics can reach breast milk and the placenta, blood plasma or accumulate inside cells. Although some animal studies suggested that these ubiquitous particles might have health effects, there was a lack of analysis in humans that had observed this link. This has changed following the publication of an article this week in the medical journal New England Journal of Medicine.
A team led by Raffaele Marfella, from the University of Campania, in Italy, explains in their study how they analyzed 257 patients who went to three hospitals in the Naples region to undergo a surgical procedure to treat the accumulation of atherosclerotic plaque in the carotid artery, in the neck. This buildup can cause clogged arteries, which increases the risk of cardiovascular problems. Those responsible for the study took samples of these plates and analyzed the presence of micro and nanoplastics. Their results show that 58% of the patients had traces of these plastic particles and, following monitoring those who had and those who did not, they observed that, in those who had plastic, the accumulated risk of dying from any cause , heart attack and stroke multiplied by 4.5.
“It is a conclusive result and opens a new vision regarding the contaminants to which we are exposed and do not see,” says Jaume Marrugat, a researcher at the Hospital del Mar Medical Research Institute in Barcelona, who did not participate in the study. Although the results do not allow us to establish a cause and effect link, there are clear factors that point in that direction. Markers of inflammation, which show the body’s response to what it considers a threat and which increases the risk of heart disease, were higher in people with nanoplastics in the carotid. “This study highlights the importance of inflammation in arteriosclerosis, because we are used to thinking regarding cholesterol or hypertension as risk factors that produce this deterioration, but they are all inflammatory processes, like the one seen produced by nanoplastics,” points out Enrique Gutiérrez, cardiologist at the Gregorio Marañón University Hospital in Madrid. Furthermore, “the carotid is an artery and the heart is also irrigated by arteries, the coronary arteries, so we can extrapolate that what happens in the carotid will also happen in the coronary artery,” concludes Marrugat.
Other studies have observed that people who work exposed to plastic pollution have a higher risk of suffering from cardiovascular diseases. In animal models, it had also been seen how nanoplastics, following being ingested or inhaled, are easily distributed throughout the body through the bloodstream and accumulate in well-watered organs, including the heart.
It is a study with a relatively small number of patients and the authors themselves recognize the possibility of a risk of contamination in the samples used. But, if confirmed, the results are worrying. Every year, nearly 400 million tons of plastics are produced each year and are used in products that are everywhere. A recent study published in the journal PNAS showed that around a quarter of a million plastic nanoparticles might be found in each one-litre plastic bottle. The particles that are released from a water bottle when it is heated or when the cap is opened and closed can also continue to divide to almost infinity. The team led by Marfella observed that most of the particles detected were below 200 nanometers and that the smaller the size, the easier it was to colonize organs or even cells.
In a relatively new field of study, there are still important unknowns. The researchers saw no differences in the presence of nanoplastics in patients living in different regions. “We don’t have any hypotheses for now. [sobre por qué unos pacientes acumulan nanoplásticos en sus placas de ateroma y otros no]but we are preparing larger studies to explore the association between exposure to plastics and the accumulation of micro- and nanoplastics in tissues,” says Francesco Prattichizzo, researcher at IRCCS MultiMedica and co-author of the study.
These future studies will also serve to understand the weight of nanoplastics compared to other risk factors. As the authors of the study comment, during the last decades, at a time when the population’s exposure to plastics has increased greatly, the prevalence of cardiovascular diseases has decreased.
New analysis techniques have made it possible to begin to detect the presence of plastics in places where it was previously unthinkable and it is now possible to identify the different types of particles that can accumulate in the body. In this way, it will be possible to know where they arrive from, the different risks posed by each type of particle and what preventive measures can be established in the face of what might be a global health problem, if results such as those published by the Italian team are confirmed. If microplastics and nanoplastics pose a significant health problem, the use of a material that can remain in the environment for centuries, which, in most cases, has a single use and which is only recycled in one place, must be re-evaluated. 9%.
