Microplastics and nanoplastics (MNPs) are everywhere — the oceans, air, soil and food supply — but evidence of their effects on human tissues and organs has been limited mostly to preclinical analyses. In March, a prospective observational study examined carotid plaque specimens from 257 people who underwent a surgical procedure to unblock arteries — and identified MNPs (specifically, polyethylene and polyvinyl chloride) in the carotid artery plaques of more than half of all participants. The presence of these MNPs was associated with a 4.5-fold increased risk of cardiovascular events after almost 3 years of follow-up. These findings do not prove causality, but they are a cause for concern; they highlight the urgent need for further research into the key sources of human exposure to MNPs, their impact on health and the mechanisms underlying these effects.

Original reference: N. Engl. J. Med. 390, 900–910 (2024)