Physicians have issued caution regarding the potential life-threatening consequences of plastic pollution. Their concerns arise from the discovery of a significantly elevated risk of stroke, heart attack, and premature death in individuals with blood vessels contaminated by microscopic plastics.
 
In Naples, researchers analyzed fatty plaques extracted from the blood vessels of patients with arterial disease. Their findings revealed that over 50% of these plaques contained deposits tainted with minuscule particles of polyethylene or polyvinyl chloride (PVC).

Individuals with plaques containing microplastics or nanoplastics faced an almost fivefold increased risk of experiencing a stroke, heart attack, or death from any cause within the subsequent 34 months, in contrast to those with plaques devoid of plastic contamination.

While the results don't establish a direct causation between plastic particles and strokes or heart attacks, individuals with higher exposure to pollution could be at an elevated risk for other factors. Nevertheless, studies on animals and human cells indicate that these particles might play a role in such health issues.

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Given the pervasive nature of plastic pollution globally, even if significant efforts were made to reduce plastic contamination, the health improvements resulting from the cleanup might take years to materialize, according to Dr. Raffaele Marfella, the first author of the study at the University of Campania Luigi Vanvitelli in Naples.

The doctors initiated the research upon observing an increase in strokes and heart attacks among patients typically classified as low-risk. Marfella and his team speculated whether plastic pollution could contribute to vascular damage through inflammation.
 
In the New England Journal of Medicine, the doctors detail their examination of fatty plaques obtained from 304 patients experiencing atherosclerosis in the carotid arteries, which are crucial blood vessels supplying blood to the neck, face, and brain.

Atherosclerosis leads to plaque accumulation in the arteries, significantly increasing the risk of stroke. The plaques can be eliminated through a procedure known as carotid endarterectomy.
 
Analysis of the removed plaques through lab tests revealed the presence of polyethylene in 150 patients and polyvinyl chloride in 31, accompanied by signs of inflammation. Under an electron microscope, the researchers observed jagged foreign particles in the fatty deposits, most of which were smaller than a thousandth of a millimeter. The doctors monitored 257 patients for an average of 34 months after carotid plaques were removed. Individuals with plastic particles in their plaques were 4.5 times more likely to experience a stroke, heart attack, or death from any cause compared to those with plaques free from plastic pollution.

Additional research is necessary to establish the connection between plastic pollution and strokes or heart attacks, yet Marfella emphasized the importance of raising awareness about the potential threat.

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