New Research Links Microplastics and Nanoplastics in Plaque to Increased Risk of Heart Attack and Stroke
A groundbreaking study published in The New England Journal of Medicine has revealed a concerning link between microplastics and nanoplastics found in plaque and an increased risk of heart attack, stroke, and death. This is the first time that scientists have established a connection between these minuscule plastic particles, which result from degraded plastic pollution, and cardiovascular disease.
Microplastics are defined as particles smaller than 5 millimeters, while nanoplastics are even smaller and can only be seen with specialized microscopes. In recent years, their presence has become undeniable, as they have been discovered in various locations, including fresh snowfall in Antarctica, the depths of the Marianas Trench, and even human blood, breast milk, urine, and tissue.
Dr. Raffaele Marfella, a cardiology researcher at the University of Campania Luigi Vanvitelli, led the study to explore new risk factors for cardiovascular disease. Recognizing the extensive amount of degraded plastic pollution contaminating the planet, Dr. Marfella and his colleagues wondered if plastic, in the form of micro- or nanoplastics, could also harm our arteries. These plastic particles can enter the body through inhalation, ingestion, or skin contact.
To investigate the effects of these particles, the researchers focused on a group of patients scheduled for surgery due to carotid artery stenosis, a condition where plaque obstructs normal blood flow. The carotid arteries supply blood to the brain, face, and neck. The team examined plaque samples from 257 patients and monitored their health for an average of 34 months after the surgery.
The study revealed that 150 patients had plastic particles, primarily nanoplastics, in their plaque. Among these patients, 20% experienced nonfatal heart attacks, nonfatal strokes, or death from any cause during the follow-up period. In contrast, only 7.5% of patients without detectable plastic particles experienced such cardiovascular events. After adjusting for various factors, including age, sex, body mass index, and health conditions like diabetes and abnormal cholesterol, the researchers found that patients with detectable levels of plastics had nearly a five times greater risk of a cardiovascular event.
While numerous experimental studies on cells and animals have demonstrated that the presence of plastic particles increases disease risk, this study is the first to observe microplastics in human arteries in such detail. Previous studies were considered pioneering but lacked the extensive analysis and long-term patient tracking seen in this research.
However, it is important to note that this observational study can only establish an association between plastic particles and heart attack, stroke, or death. To prove causation, researchers would need to conduct a randomized, controlled trial. Unfortunately, intentionally exposing individuals to potential toxins for such a study would be unethical.
Nevertheless, the study provides valuable insights into the relationship between micro- and nanoplastics and heart disease. Dr. Martha Gulati, director of preventive cardiology at Cedars-Sinai in Los Angeles, suggests that inflammation may play a role. Cardiovascular disease, particularly heart attacks, is often triggered by an inflammatory response. The Italian researchers measured markers for inflammation in patients and found that these markers increased as the level of plastics in the plaque rose. However, further research is needed to determine if the inflammation is directly caused by nanoplastics or other factors.
While the study focused on a specific group of patients and cannot be generalized to the broader population, it lays the groundwork for future investigations. Dr. Gulati believes that measuring micro- and nanoplastics in the general population and studying who develops cardiac events could provide valuable insights. Similar studies on other types of human tissue are already in progress.
The researchers acknowledge the possibility of contamination in the lab and suggest that future studies be conducted in clean rooms, where no plastic is present except for the material under investigation.
Dr. Gulati hopes that this study and the subsequent research it inspires will spark discussions about our environment and cardiovascular health. She emphasizes that this topic receives little attention despite its significance. As plastic pollution continues to degrade and infiltrate various ecosystems, understanding its impact on human health becomes increasingly crucial.
