Microplastics in the body

Microplastics in the human body: what research shows.

In the last few years, researchers have found microplastics in human blood, lungs, brain tissue, arteries, semen, urine, and stool. The headlines move fast and the science is still young. This is a plain, honest map of what's actually known — and what you can, and can't, test for yourself.

What the research has found

2018

Microplastics detected in human stool for the first time — eight participants, every sample positive.

Schwabl et al., Annals of Internal Medicine

2022

Microplastics found in human blood — the first study to detect plastic particles circulating in the bloodstream.

Leslie et al., Environment International

2024

Microplastics in carotid-artery plaque linked to a 4.5x higher risk of heart attack, stroke, or death over ~34 months.

Marfella et al., New England Journal of Medicine

2024

Microplastics detected in human urine and kidney tissue via micro-Raman spectroscopy.

Science of the Total Environment

2025

Decedent brain tissue found to hold micro- and nanoplastics at far higher concentrations than other organs — the "plastic spoon" study.

Nature Medicine

2025

Microplastics found in human semen and ovarian follicular fluid.

Human Reproduction / press coverage

A note on the science: this field is new, and in 2025–2026 some high-profile body-microplastics studies drew scrutiny over contamination controls and methodology. Treat single dramatic numbers with caution. The broad finding — that microplastics are widespread in the human body — is well supported; the precise quantities are still being worked out.

What you can test for

Start with what you can control.

You can't un-drink the last decade — but you can see what you're drinking now. The $50 at-home kit tests your water for microplastics in about 15 minutes.

Not a medical or diagnostic test. The Water Test makes at-home kits that visualize and count particles in a sample. Nothing here diagnoses or assesses any disease or health condition. For health concerns, talk to a doctor.