# Microplastics

Microplastics are solid plastic particles smaller than 5 mm (including nanoplastics, which are sub-micron). They come from larger plastic debris breaking down, plus synthetic textiles, tire wear, and personal-care products. They are turning up inside us. They have been detected in human blood, placenta, and breast milk. And in a 2024 NEJM study (Marfella and colleagues), they were found inside the fatty plaques of carotid arteries. In that study, patients with detectable plaque microplastics had a significantly higher risk of heart attack, stroke, and death over about 34 months. How might they harm you? Proposed routes include local inflammation, hormone disruption from adsorbed additives (like phthalates and bisphenols), and oxidative stress. But the dose-response in humans is still poorly mapped. The clinical significance and any 'safe' level are not established, and there is no proven way to reduce them beyond cutting your dietary and inhaled exposure.

## Sources

- Marfella R, Prattichizzo F, Sardu C, et al.. (2024). Microplastics and nanoplastics in atheromas and cardiovascular events. New England Journal of Medicine. https://doi.org/10.1056/NEJMoa2309822

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_Canonical: https://longevity-austria.com/en/glossary/microplastics · Part of Longevity Cities · Updated 2026-06-22_