Question:
I’m worried about the amount of minute plastics in my cup of tea every time I use a teabag. I’ve written to various manufacturers and only one says its bags are plastic free. Can you comment please?
Answer:
You’re right to be curious about what’s steeping in your teacup alongside the tea leaves. While tea feels like one of the simplest pleasures in life, many teabags hide a modern twist – plastic.
Traditionally, teabags were made entirely from paper. But to help them keep their shape and stop splitting in hot water, many manufacturers now seal them with polypropylene, a common thermoplastic. Some premium pyramid-shaped “silken” bags are even made wholly from nylon or similar polymers. Increasingly, manufacturers are also using polylactic acid (PLA) – a plant-derived polymer often marketed as biodegradable or compostable. Although PLA is derived from plants and breaks down more readily under industrial composting facilities, it is still a plastic polymer. And importantly, whether the teabag is made from polypropylene, nylon, or PLA, studies show these materials can release microscopic plastic particles into hot water.
A widely cited 2019 Canadian study found just one plastic teabag steeped in hot water released about 11.6 billion microplastic and 3.1 billion nanoplastic particles into a single cup. That’s billions with a “b”, and the particles matched the plastics used in the teabags themselves.
Other research has since explored what kinds of plastics leach out, how we measure them, and whether microwaving or brewing methods alter the numbers. Though detection techniques differ, the consensus is clear: plastic-containing teabags are capable of releasing microplastics into tea.
Microplastics, and even smaller nanoplastics, are now found everywhere, from the air we breathe to the food and water we consume, noted a comprehensive 2024 review in the journal Science of the Total Environment. Research has shown they can enter the bloodstream. Indeed, human studies have found microplastics in eight of our 12 organ systems, including cardiovascular, digestive, endocrine, respiratory, lymphatic, reproductive, integumentary (skin) and urinary systems. They’ve also been detected in breast milk, meconium (a newborn’s first stool), semen, urine, sputum and faeces. Once inside the body, some may pass straight through, but others appear capable of disrupting hormone signals, crossing cell membranes, inducing inflammation, oxidative stress, metabolic disruption, and even damaging DNA. However, scientists caution we still don’t fully understand the effects of everyday, real-world exposure. Because most lab studies use higher doses than we normally encounter, and microplastics in the environment change over time, interacting with chemicals, bacteria and other materials, this makes their real-world impact difficult to predict.
Still, the fact that almost all teabag types contribute to this exposure underscores the value of making informed choices. Although the numbers released from a single plastic teabag are enormous, we don’t yet know how this compares with the overall “plastic diet” most of us consume daily. It’s likely your teabag is only one of many routes of exposure, but it’s an easy one to control:
•Check the label: Some brands, including a few big New Zealand names, now proudly state their teabags are plastic-free. Transparency is improving thanks to consumer demand (remember PLA counts as a microplastic source, even if it is a plant-derived material).
•Contact the manufacturer: If the packaging isn’t clear, a quick call or email can confirm whether plastic is used.
•Switch to loose-leaf: This is the simplest way to sidestep plastic in teabags altogether. Brew your tea in a pot or use a reusable infuser, and you’ll avoid the packaging problem while enjoying excellent flavour.
At present, there’s no comprehensive public list of which tea producers use plastics and which don’t, but the trend is definitely towards phasing them out.
So, yes, your teabag could be adding plastics to your cuppa. But it’s also part of a much bigger picture of microplastic exposure that extends far beyond the kitchen. While the health risks are still being unravelled, making small, informed choices – like opting for plastic-free teabags or loose-leaf tea – is one practical way to reduce your personal exposure.
And it might even make that next cup of tea taste a little sweeter.
Email your nutrition questions to listenerlife@aremedia.co.nz
