Microplastics were found inside arterial plaque — and linked to more heart attacks and strokes

Microplastics have been detected in human blood, lungs and placenta for a few years now, but this landmark New England Journal of Medicine study was the first to find them embedded directly in arterial plaque — and to link that finding to actual cardiovascular events, not just presence in tissue.

What the study did

Researchers analysed carotid artery plaque removed during surgery from patients with carotid artery disease, testing the tissue for microplastics and nanoplastics, then followed those patients over several years to track cardiovascular outcomes — heart attack, stroke and death.

What they found

Polyethylene was detected in the carotid plaque of 58.4% of patients (150 total), at a meaningful average concentration. Patients whose plaque contained microplastics had a substantially higher rate of a composite of heart attack, stroke or death during follow-up compared with patients whose plaque did not — a real, measured clinical outcome difference, not just a laboratory curiosity.

Why this moved the field, and what still needs proving

A large 2024 European Heart Journal review that followed this study lays out the proposed mechanisms — oxidative stress, platelet aggregation, cellular senescence and inflammatory responses in the endothelium — through which microplastics could plausibly contribute to atherosclerosis, rather than merely being an inert bystander found alongside it. That said, this remains an association in a specific surgical population, not proof that removing microplastic exposure would reduce cardiovascular risk — that causal question is still open and being actively studied.

What you can actually act on today

While a validated way to measure or reduce your own microplastic exposure specifically for cardiovascular benefit doesn’t exist yet, common-sense exposure reduction (limiting plastic food/drink containers especially when heated, filtering drinking water, reducing highly processed and plastic-packaged food) is low-cost and plausible, without requiring you to wait for the causal question to be fully settled.

In the meantime, the established cardiovascular risk markers this research is trying to explain — ApoB, blood pressure, hs-CRP — are exactly what Misi’s biomarker tracking already prioritises; that remains the highest-yield place to focus while microplastics research continues to develop.