A groundbreaking study published in the New England Journal of Medicine has confirmed what many scientists feared: microplastics are not just in our environment, but they are embedding themselves in human tissue. For the first time, researchers have directly linked the presence of tiny plastic particles in arterial plaque to a significantly increased risk of heart attack, stroke, and early death.
In March 2024, a team of researchers led by Dr. Raffaele Marfella at the University of Campania Luigi Vanvitelli in Naples, Italy, released findings that changed how cardiologists view pollution and heart health. The study focused on 257 patients who were undergoing a surgical procedure called a carotid endarterectomy. This surgery is performed to remove built-up plaque from the carotid arteries, which supply blood to the brain, to prevent strokes.
Instead of discarding the removed plaque, the researchers analyzed it using two powerful methods: pyrolysis-gas chromatography-mass spectrometry and electron microscopy. The results were startling. They detected measurable amounts of polyethylene in the plaque of 150 patients, which represents nearly 60% of the study participants. Furthermore, 31 of those patients also had measurable amounts of polyvinyl chloride, or PVC, alongside the polyethylene.
These were not vague traces. The electron microscopy revealed visible, jagged-edged foreign particles embedded within the plaque macrophages and foam cells. These are the immune cells responsible for clearing debris from the arteries. The images provided concrete visual evidence that our bodies are attempting, and failing, to digest these synthetic invaders.
The most alarming aspect of Dr. Marfella’s study was not just the presence of plastic, but the health outcomes associated with it. The research team followed up with the patients for an average of 34 months after their surgery. They tracked incidences of nonfatal heart attacks, nonfatal strokes, and death from any cause.
The statistics revealed a massive discrepancy between patients with plastics in their arteries and those without. Patients with microplastics or nanoplastics in their arterial plaque were 4.5 times more likely to experience a heart attack, stroke, or death within that three-year window compared to patients whose plaque was plastic-free.
This hazard ratio remained high even when researchers accounted for other risk factors such as diabetes, high blood pressure, and smoking habits. This suggests that the plastic itself serves as an independent and potent risk factor for cardiovascular disease.
The study suggests that the physical presence of microplastics destabilizes arterial plaque. Plaque is a waxy substance made of cholesterol, fat, calcium, and other substances found in the blood. When plaque is stable, it narrows arteries but stays in place. When it becomes unstable, it can rupture. A rupture causes a blood clot to form, which can block blood flow to the heart or brain.
The researchers hypothesize that the jagged shards of microplastics trigger chronic inflammation. In the patients with plastic-laden plaque, the team found significantly higher levels of inflammatory biomarkers. Essentially, the body perceives the plastic as a foreign invader and launches an immune response that never ends. This constant state of inflammation weakens the fibrous cap of the plaque, making it prone to breaking open and causing a catastrophic event.
To understand the risk, it is important to understand the materials found inside these patients.
Polyethylene (PE) This was the most common plastic found, appearing in nearly 60% of patients. Polyethylene is the most widely produced plastic in the world. It is used to create:
Polyvinyl Chloride (PVC) Found in about 12% of the patients, PVC is generally more rigid. It is commonly found in:
The ubiquity of these materials makes exposure almost impossible to avoid completely. As these items break down in the environment, they turn into microplastics (smaller than 5 millimeters) and nanoplastics (smaller than 1 micrometer). Nanoplastics are particularly dangerous because they are small enough to pass through the intestinal lining and enter the bloodstream.
How do plastic bags and pipes end up in the carotid artery? Research indicates three primary pathways for entry into the human body:
While the New England Journal of Medicine study is pivotal, scientists note that it establishes correlation rather than direct causation. It is possible that people with higher levels of plastic in their bodies lived in areas with higher air pollution, or had lower socioeconomic status, which are also risk factors for heart disease.
However, the biological evidence (inflammation markers and visible particles inside immune cells) strongly supports the theory that the plastic is doing direct damage. Future studies will likely focus on other arteries, such as the coronary arteries, to see if the findings are consistent throughout the circulatory system.
While you cannot remove microplastics already in your system, you can limit new intake. Experts recommend specific changes to reduce your daily load:
Can doctors test me for microplastics in my arteries? Currently, there is no standard blood test or scan to detect microplastics in a living patient’s arteries. The study identified them by analyzing plaque surgically removed from the body.
Does donating blood remove microplastics? Some preliminary research suggests that plasma donation or blood donation might lower the concentration of “forever chemicals” (PFAS) in the blood, but there is currently no conclusive evidence that it effectively removes physical microplastic particles from arterial plaque.
Are nanoplastics worse than microplastics? Likely, yes. Nanoplastics are microscopic enough to bypass the body’s protective barriers, including the gut lining and the blood-brain barrier. This allows them to infiltrate cells and organs in ways larger microplastics cannot.
Did the study mention specific brands of plastic? No. The study identified the chemical composition of the plastic (polyethylene and PVC) but could not trace the particles back to specific brands or products, as the particles had degraded into microscopic fragments.