What microplastics are
Microplastics are plastic fragments smaller than 5 mm, produced when larger plastic items break down through heat, light, abrasion and age. Nanoplastics are smaller still. They are not an ingredient anyone adds — they are what plastic becomes as it wears.
What is well established
- They are widespread in food, drinking water, air and household dust.
- They have been detected in human tissue and blood in multiple studies.
- Plastic items shed more as they are heated, scratched or flexed.
What is still uncertain
Researchers have not settled on how much exposure causes measurable harm in humans, or which particle sizes and polymer types matter most. Laboratory and animal studies raise concerns around inflammation and the additives carried by plastics, but translating those results to everyday human exposure is genuinely unfinished work.
Anyone claiming certainty in either direction is going beyond the evidence.
Why reducing exposure is still reasonable
When a risk is plausible, poorly quantified, and cheap to reduce, reducing it is a sensible default. Most microplastics swaps cost nothing in convenience and usually improve the object: glass, steel and wood outlast the plastic they replace.
This is the whole basis of what we make. Not fear — just better versions of things you already own.