A new study published in The New England Journal of Medicine has found compelling evidence linking microplastics (MNPs) in the human body to a higher risk of severe cardiovascular events, such as heart attacks and strokes. This study marks the first time microplastics have been detected in human arterial plaques, highlighting a potential new risk factor for heart disease
Microplastics: A New Cardiovascular Threat?
Microplastics, tiny particles of plastic less than 5 mm in size, are becoming a growing concern for environmental and human health. Although they are known to enter the human body through ingestion, inhalation, and skin exposure, their impact on cardiovascular health has not been well studied—until now.
Researchers from multiple institutions in Italy conducted a prospective, multicenter observational study involving 304 patients undergoing carotid endarterectomy, a surgical procedure to remove plaque from the carotid arteries. The aim was to determine whether microplastics are present in atherosclerotic plaques and if they contribute to cardiovascular disease risk.
Study Design and Methodology
The study used advanced techniques like pyrolysis–gas chromatography–mass spectrometry, stable isotope analysis, and electron microscopy to detect microplastics in the carotid plaques of patients. In addition, inflammatory biomarkers were assessed to understand the potential mechanisms by which microplastics could increase cardiovascular risk.
Key findings from the study include:
- High Detection Rates of Microplastics: Out of 304 patients, 58.4% had detectable levels of polyethylene, a common type of plastic, in their carotid artery plaques. Additionally, 12.1% of patients had measurable amounts of polyvinyl chloride (PVC), another plastic type.
- Increased Risk of Major Cardiovascular Events: The study revealed that patients with microplastics in their arterial plaques were 4.5 times more likely to suffer a major cardiovascular event, such as a heart attack, stroke, or death, within a 34-month follow-up period compared to those without microplastics. The hazard ratio for these patients was 4.53, with a 95% confidence interval of 2.00 to 10.27 (P < 0.001).
- Inflammatory Response and Tissue Damage: The study also noted elevated levels of inflammatory markers, such as interleukin-18, interleukin-1β, tumor necrosis factor α (TNF-α), and interleukin-6, in patients with microplastics in their plaques. These markers indicate a heightened inflammatory response, which could accelerate the progression of cardiovascular diseases.
Why Are Microplastics in Arteries Dangerous?
Microplastics have been detected in various human tissues before, including the placenta, lungs, liver, breast milk, urine, and blood. However, this is the first study to identify their presence in human atherosclerotic plaques. The researchers believe that microplastics could enter the bloodstream through the digestive tract or lungs and become embedded in arterial walls. Once there, they may trigger oxidative stress, inflammation, and cell damage, all of which contribute to the development of cardiovascular diseases.
The presence of polyethylene and PVC, in particular, suggests that these plastics may be especially prone to accumulating in vascular tissues. This finding raises questions about the sources of these microplastics, which are widely used in everyday products such as food packaging, water bottles, and cosmetics.
Implications for Public Health and Future Research
The study’s findings point to microplastics as a potential new risk factor for cardiovascular disease, which remains the leading cause of death worldwide. “Our results suggest that microplastics could play a role in the development and progression of cardiovascular disease,” said Dr. Raffaele Marfella, the lead author of the study. “However, more research is needed to establish causality and understand the mechanisms involved.”
The authors emphasize the need for future studies to explore how microplastics are entering human bodies, whether through ingestion, inhalation, or other means, and to determine the long-term effects of these particles on cardiovascular health. There is also a need to investigate whether certain populations are more susceptible to the adverse effects of microplastics and what preventive measures can be taken.
Call to Action: Addressing the Microplastic Problem
With the increasing production and widespread use of plastics, the potential health impacts of microplastics cannot be ignored. Policymakers, researchers, and healthcare professionals must collaborate to assess the full extent of the threat posed by microplastics and to develop strategies to mitigate their impact on human health.
Reducing plastic pollution, improving waste management, and promoting alternatives to plastic use are crucial steps in minimizing human exposure to microplastics. As new evidence emerges, it will be vital for global health guidelines to consider microplastics as a potential risk factor for cardiovascular and other diseases.
Conclusion
This study opens up new avenues of research into the impact of environmental pollutants on human health. It also underscores the urgent need for further investigation into how microplastics may contribute to cardiovascular disease, potentially reshaping how we understand, prevent, and treat these conditions in the future.
Source:
Marfella, R., Prattichizzo, F., Iovino, P., & Paolisso, G. et al. (2024). Microplastics and Nanoplastics in Atheromas and Cardiovascular Events. The New England Journal of Medicine, 390(10), 900-910. DOI: 10.1056/NEJMoa2309822.
