Microplastics in atherosclerotic plaques increased the risk of heart attack and stroke
Researchers from Italy have found that the presence of microplastics in carotid atherosclerotic plaques increases the risk of a combination of myocardial infarction, stroke, or death from any cause. As reported in The New England Journal of Medicine, polyethylene and polyvinyl chloride are mostly found in plaques.
Several studies have shown that microplastics and nanoplastics enter the human body through the gastrointestinal tract, lungs, and skin, where they interact with tissues and organs. Data from in vitro studies suggest that microplastics promote oxidative stress, inflammation, and apoptosis in endothelial cells. Animal models have shown that such exposure leads to changes in heart rate, impaired cardiac function, myocardial fibrosis, and endothelial dysfunction. However, it is not known how clinically relevant these observations are for humans. At this time, there is no evidence that microplastics can cause vascular lesions in humans.
A team of scientists led by Raffaele Marfella of the University of Naples Luigi Vanvitelli conducted a prospective study that evaluated the presence of ethog microplastic in surgically removed carotid plaques using pyrolytic gas chromatography-mass spectrometry, stable isotope analysis and electron microscopy. Researchers then studied the association between the presence of microplastics in the plaque and the combined outcome of myocardial infarction, stroke, or death from any cause.
A total of 312 patients undergoing surgical removal of carotid plaque were studied, with 257 patients who were followed for an average of 33.7 months in the final analysis. In 150 patients, they found appreciable amounts of polyethylene in the removed plaque (21.7 ± 24.5 micrograms per milligram of plaque), and in 31 patients, they found measurable amounts of polyvinyl chloride (5.2 ± 2.4 micrograms per milligram of plaque). However, physicians did not clearly differ in the frequency of microplastic detection according to patient residence or medical center location.
Visualization by transmission electron microscopy in ten randomly selected patients showed the presence of jagged-edged particles in foamy plaque macrophages. Almost all particles were smaller than one micrometer. Scanning electron microscope showed reduced carbon and oxygen content in these particles and high chlorine content. Stable isotope analysis showed that the ratio of carbon-13 to carbon-12 varied between patients without any obvious pattern. Linear regression analysis revealed a positive correlation between the amount of polyethylene present and the expression levels of interleukin-18, interleukin-1β, interleukin-6, and tumor necrosis factor-α, as well as CD3- and CD68-cell levels. The amount of collagen was reduced in this case.
Patients with micro- or nanoplasty in carotid atherosclerotic plaque had a higher risk of heart attack, stroke, or death from any cause than patients without these substances in the plaque (hazard ratio 4.53, p < 0.001). The unadjusted risk ratio was 2.84 (p = 0.007).
The results of this study indicate that micro- and nanoplastics can significantly increase the risk of serious cardiovascular events. These findings suggest a link between environmental pollution and poorer public health, so they are important for developing interdisciplinary programs to reduce pollution.
Recently, we told you how you can purify water from microplastics at home. Chinese scientists have found that boiling water removes more than 80 percent of microplastics.