How to tell if your tea bags contain plastic
Look at the shape, the seal and the wording on the box. Or skip the question with loose-leaf tea.
By PlasticFreeHome Research Team · Reviewed by Khalid · Updated 21 October 2026 · 1 min read
The quickest clues are the bag's shape and how it's closed: silky "pyramid" bags are often plastic mesh, and flat paper bags with crimped edges are usually heat-sealed with plastic. Loose-leaf tea avoids the question entirely.
Clues on the bag
- Pyramid or silky mesh bags are usually nylon, PET or PLA (a plant-based plastic).
- Flat bags with sealed, crimped edges are usually paper held together with a thin layer of polypropylene that melts to seal the bag.
- Folded bags closed with a staple or string, with no sealed edge, are the most likely to be plastic-free.
Clues on the box
- "Plastic-free" may refer only to the outer wrapper. Check that it covers the bag itself.
- "Biodegradable" or "plant-based" bags are often PLA, which is still plastic under our definition.
- Brands that name every material in the bag are more trustworthy than those that don't.
How much plastic reaches your cup?
A widely reported 2019 study counted billions of particles in a single cup from plastic mesh bags. Germany's risk assessor re-tested it and found the counts were probably far too high and that most particles were plastic by-products, not microplastics. So the exposure is real in principle, but its size is still debated.
We plan to test tea bags in our first study; see the research calendar.
Sources
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Top swaps in drinks & snacks
Bottled water → tap water in a steel bottle
Bottled water carries hundreds of thousands of plastic particles per litre. UK tap water is cheap and safe.
Swap first · about 3.0 kg of plastic a year
Plastic tea bags → loose-leaf or plastic-free bags
Many tea bags are sealed with polypropylene or made of plastic mesh. Hot water plus plastic, several times a day; how much reaches your cup is still debated.
High priority · about 120 g of plastic a year
Plastic coffee pods → cafetière or moka pot
One pod a day is over a kilo of hard-to-recycle packaging a year, and hot pressurised water runs through plastic.
High priority · about 1.0 kg of plastic a year