More than half of the plaques from clogged arteries contain plastic

Plastics are now ubiquitous, with tiny fragments discovered in several major human organs, including in the placenta (see our recent article on the subject here).

This infiltration of microscopic particles into our tissues raises concerns about potential health risks. Researchers have studied the effects of microplastics in mini-replicas of organs and in mice to understand their impact on the human body. However, the concentrations of microplastics used in these studies might not reflect real-life exposure, and few studies have been conducted on humans.


A recent study conducted in Italy revealed the presence of microplastic fragments in fatty deposits surgically extracted from patients who underwent surgery to unclog their blocked arteries. The team behind this study, led by Raffaele Marfella, a medical researcher at the University of Campania in Naples, wondered about the comparison of stroke, myocardial infarction, and death risks between patients with microplastics in their plaques and those without.

Out of 257 patients followed for 34 months, nearly 60% had measurable amounts of polyethylene in the plaques removed from their fat-thickened arteries, and 12% also had polyvinyl chloride (PVC) in the extracted fatty deposits.

With microplastics previously detected in individuals' blood, researchers were understandably concerned about heart health. Laboratory studies suggest that microplastics can trigger inflammation and oxidative stress in heart cells, impair heart function, and alter heart rhythm.

In the study, patients with microplastics in their removed plaques were twice as likely to have suffered a stroke, a non-fatal myocardial infarction, or to have died from any cause after 34 months, compared to those without detectable microplastics in the surgically removed plaques.

The amount of microplastics, and even smaller nanoplastics, was measured using a technique called "pyrolysis–gas chromatography–mass spectrometry," and their presence was confirmed by another method, stable isotope analysis, which can distinguish the carbon from human tissues and that from plastics made from petrochemical products.

Microplastics were also visible under powerful microscopes: researchers observed plastic fragments with jagged edges inside immune cells called macrophages, and within the fat plaques. By examining the tissue samples, the team also found higher levels of inflammatory markers in patients with microplastics in their plaques.

However, it should be noted that an observational study like this cannot definitively conclude that microplastics are responsible for subsequent cardiac effects; only that there is an association. The study did not account for other cardiovascular disease risk factors, such as smoking, physical inactivity, and air pollution.