Pollution & health
Nanoplastics
Plastic particles smaller than one micrometre — small enough to cross biological membranes — detected in ecosystems and human blood, placenta and breast milk.
Definition
Nanoplastics are plastic particles smaller than 1 micrometre (some definitions use 1–100 nm), formed by the fragmentation of larger plastic debris or manufactured intentionally for industrial uses. Their size gives them colloidal behaviour and the ability to penetrate biological barriers — they have been detected in human bloodstream, placenta and breast milk, and can carry adsorbed pollutants into tissues.
References
<1 µm definition, sources, biological barrier penetration
size distinction, evidence status
Overview
What it means
Nanoplastics are the least visible and hardest to measure fraction of plastic pollution: too small for most filtration and monitoring, potentially more biologically active per mass than microplastics, and essentially impossible to remove once dispersed.
How it is used
An emerging research and regulatory frontier — featured in global plastics treaty discussions, drinking-water studies and chemical safety assessments; detection methods (e. g. , advanced spectroscopy) are rapidly developing.
Why it matters
If microplastics made plastic pollution visible, nanoplastics make it intimate: their presence inside the human body reframes plastic as a health issue, strengthening the case for upstream prevention.
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