As Susan Gardner, Director of the Ecosystems Division at the United Nations Environment Programme, remarked in June,
“It’s probably safe to say that microplastics are just about everywhere.”
Even Gardner might be surprised by the latest findings from a group of Italian researchers, who have discovered these tiny flecks of plastic in an unexpected place: human arteries.
Published in the New England Journal of Medicine, the 2025 report details an observational study that tracked patients undergoing procedures to remove fatty deposits from blocked arteries. The study’s findings indicate that microplastics, which are defined as particles smaller than 5 mm, and nanoplastics, smaller than 1000 nanometers, have made their way into the human body, with potentially serious health consequences.
Microplastics: A Growing Environmental and Health Concern
The study highlights a troubling trend: the ever-increasing production of plastics, which is expected to continue unabated until at least 2050. The researchers noted that plastics can pollute the environment through various channels such as ocean currents, atmospheric winds, and terrestrial phenomena. Once released, plastics degrade into smaller particles, becoming microplastics and nanoplastics that are pervasive in our surroundings.
According to the study, these microplastics are not just found in the environment but also in everyday items within our homes. As reported by Food & Wine, microplastics can shed from nonstick cookware, takeout containers, soda bottles, and even cleaning sponges, making their way into the food we consume.
The Study: Tracking Microplastics in Human Arteries
The research team focused on patients who had undergone a procedure known as “carotid endarterectomy” for asymptomatic carotid artery disease. This procedure involves the removal of plaque from narrowed arteries. The team analyzed the extracted plaque for the presence of microplastics and nanoplastics, as well as inflammatory biomarkers in the 257 patients involved in the study.
The results were striking: polyethylene, the most common plastic worldwide, was detected in the carotid artery plaque of 150 patients, representing 58.4% of the participants. Additionally, 31 patients, or 12.1%, had measurable amounts of polyvinyl chloride, another widely used synthetic plastic, in their plaque.
Health Implications: A New Risk Factor?
The presence of these plastics in the body is more than just a curiosity. The study found that patients with micro- and nanoplastics in their carotid artery plaque were over four times as likely to suffer from myocardial infarction, stroke, or death from any cause within a 34-month follow-up period compared to those without detected plastics.
The researchers explained that micro- and nanoplastics can enter the human body through ingestion, inhalation, and skin exposure, triggering toxicological effects. Preclinical models suggest these plastics may contribute to cardiovascular diseases by promoting oxidative stress and inflammation, leading to conditions such as altered heart rate, cardiac-function impairment, myocardial fibrosis, and endothelial dysfunction.
“The clinical relevance of these findings is unknown,”
the team cautioned, emphasizing the need for further research to fully understand the impact of microplastics on human health.
Broader Context: Microplastics in the Human Body
This study adds to a growing body of research indicating that microplastics are present in nearly every part of the human body, including the lungs, blood, placenta, and liver. Previous studies have suggested that these particles could contribute to liver damage and other health issues.
The discovery of microplastics in human arteries raises new questions about the long-term health implications of plastic pollution. As the production and use of plastics continue to rise, understanding their impact on human health becomes increasingly urgent.
Looking Forward: Addressing the Plastic Problem
The findings of this study underscore the need for comprehensive strategies to address plastic pollution, both in terms of reducing plastic production and improving waste management. Policymakers, environmental organizations, and the public must work together to mitigate the spread of microplastics and protect human health.
As research continues to uncover the pervasive nature of microplastics, it is clear that these tiny particles pose a significant challenge to both environmental and public health. The next steps will require coordinated global efforts to reduce plastic pollution and further investigate the health effects of microplastics.
