Plastics and Microplastics
Microplastics have been found in blood, lung tissue, breast milk and placenta. That is established and it is genuinely remarkable. What it means for health is much less settled, and this page tries to hold both of those at once.
What is known
Plastic breaks into progressively smaller fragments rather than disappearing. Below five millimetres these are microplastics, and below a micron, nanoplastics, which are small enough to cross membranes that larger particles cannot.
They have been detected in human tissue in multiple independent studies. Most people are ingesting and inhaling some quantity continuously, and indoor air and dust are a larger route than most people expect, probably larger than drinking water for many households.
Plastics also carry additives, and those additives are often the more plausible concern. Phthalates, bisphenols and flame retardants are not the plastic itself but travel with it.
What is not known
This is where honesty is required, because the gap between the headlines and the evidence is wide.
We do not have good human data on what a given level of accumulation does over a lifetime. We do not have an established threshold below which it is safe or above which it is not. We cannot currently connect an individual's symptoms to their particle burden, and there is no test worth paying for that claims to.
A reasonable position
The evidence of exposure is strong. The evidence of harm at ordinary environmental levels is suggestive rather than settled, and animal studies at high doses show effects that may or may not translate.
That justifies reducing exposure where it is cheap and easy to do so. It does not justify anxiety, and it does not justify spending money on products that claim to remove them from your body, because nothing has been shown to do that.
Where yours are actually coming from
- Indoor dust and air. Synthetic carpet, upholstery and clothing shed constantly. For most people this is the largest route and the least discussed.
- Heated and stored food. Heat, fat and time all increase migration. Microwaving in plastic containers is the clearest example.
- Bottled water. Substantially higher particle counts than tap water in most comparisons, and the bottle itself is the reason.
- Tea bags. Many are sealed with polypropylene, and steeping at boiling point does what you would expect.
- Non-stick cookware past its best. Scratched and worn surfaces shed, which is a reason to replace rather than to panic.
What is worth doing
Five changes, all cheap, in rough order of effect.
- Never heat food in plastic. Glass or ceramic. If you do one thing on this page, this is it.
- Tap water in a glass or steel bottle rather than bottled. Filter if your local water warrants it.
- Vacuum and damp dust more often. Unglamorous, and it directly addresses the biggest route.
- Loose leaf tea, or bags from a brand that states they are plastic free.
- Replace scratched non-stick and avoid preheating it empty.
What is not worth doing: any supplement, binder or cleanse marketed for microplastics. There is no evidence any of it works, and the marketing relies on the fear rather than the data.
