Plastic Inside the Heart: New Study Links Microplastics to Cardiovascular Risk

Redacción HC
05/06/2025

In an alarming discovery, researchers have detected microplastics and nanoplastics embedded in human arterial plaque, raising urgent questions about how invisible environmental pollutants could be impacting heart health. A major observational study published in The New England Journal of Medicine has identified a potential connection between these plastic particles and a quadrupled risk of heart attack, stroke, or death in patients with atherosclerosis.

The study marks the first clinical evidence linking the presence of microplastics in human tissues to severe cardiovascular events, pushing the debate on plastic pollution beyond environmental concerns and into the realm of public health.

From Ocean Waste to Arterial Plaque

For years, the presence of microplastics—plastic fragments less than 5 mm in size—has been documented in marine ecosystems, drinking water, and even human blood. However, their impact on human cardiovascular health remained speculative until now.

This new study, led by a consortium of Italian researchers including Raffaele Marfella and Francesco Prattichizzo, analyzed carotid artery plaque samples from 257 patients undergoing surgery for asymptomatic stenosis. The researchers asked a critical question: Are microplastics simply passing through our systems—or are they embedding in our bodies and putting our lives at risk?

How the Study Was Conducted

The research team employed cutting-edge forensic techniques—including pyrolysis-GC-MS, stable isotope analysis, and electron microscopy—to detect and confirm the presence of plastic particles.

Key Methodological Details:

• Sample Size: 257 patients (from an initial pool of 304)
• Follow-up Duration: Average of 33.7 months
• Plastics Identified: Polyethylene (in 58.4% of cases) and polyvinyl chloride (PVC, in 12.1%)
• Particle Location: Within macrophages and extracellular matrix of plaque
• Validation: Confirmed by microscopy and isotopic signatures of petrochemical origin

The study also tracked inflammatory markers such as IL-1β, IL-6, and TNF-α, which were found in higher concentrations in patients with plastic-positive plaques, indicating an active immune response potentially linked to atherogenesis.

Plastic and Heart Disease: A Dangerous Link

A Startling Risk Increase

The presence of microplastics in arterial plaque was strongly associated with cardiovascular events:

• 30 major events (heart attack, stroke, or death) occurred in patients with microplastics
• Only 8 events occurred in those without
• Adjusted hazard ratio (HR) of 4.53 (95% CI: 2.00–10.27; p < 0.001)

This means patients with detectable microplastics in their plaque had over four times the risk of a serious cardiovascular outcome.

Inflammation and Immune Activation

The biological mechanism appears to involve chronic inflammation, a known driver of atherosclerosis. Plastic particles were linked with:

• Elevated inflammatory cytokines (IL-1β, IL-6, TNF-α)
• Increased immune cell markers (CD3 for T-cells, CD68 for macrophages)
• Collagen deposits indicating plaque instability

These findings reinforce theories developed from animal studies, now validated for the first time in humans.

Practical Implications for Health and Policy

A Wake-Up Call for Public Health

This study's results may redefine plastic pollution as a direct threat to human cardiovascular health. The implications are vast:

• Regulatory bodies may need to reassess safety limits for plastic exposure in water, air, and food.
• Healthcare professionals may begin factoring environmental exposure into risk assessments for heart disease.

Medical Perspective

Physicians may soon consider microplastic load as an emerging cardiovascular risk factor, especially in urban populations or those with known plastic exposure through diet or environment.

What Can Be Done?

The study's authors recommend:

1. Larger and more diverse prospective studies
2. Environmental monitoring of MNPs in air, water, and food chains
3. Intervention trials assessing whether reducing exposure lowers health risks

They also highlight the need to develop filtration systems, dietary guidelines, and public awareness campaigns to mitigate ongoing exposure.

The Road Ahead: More Than a Plastic Problem

This study may only scratch the surface of how microplastics affect human health. Future research could investigate:

• Causal mechanisms: How exactly do these particles influence plaque formation and rupture?
• Reversibility: Can reducing plastic exposure improve cardiovascular outcomes?
• Systemic effects: Are microplastics also accumulating in other organs?

The findings also hold global relevance, particularly for regions with poor waste management and high plastic contamination—such as megacities in Latin America and South Asia—where cardiovascular disease is already a leading cause of mortality.

Final Thoughts: What Lies Beneath the Surface

As the world grapples with the environmental crisis of plastic waste, this study reminds us that the problem is not just what we throw into the oceans—it's what ends up inside us.

Microplastics may be the new frontier in cardiovascular risk, silently embedding in our arteries while we go about our daily lives. Understanding and mitigating their impact could become a defining challenge for both medicine and environmental policy in the 21st century.

Topics of interest

Health