What is in your tea? Milk, sugar, maybe honey and lemon or some masala. How about some plastic? Yes, your daily beverage might contain billions of micro-plastics, as found in research by McGill University in Montreal.
Recently, some tea manufacturers have replaced their paper teabags with plastic or 'silken' teabags. These plastic teabags are harmful to both the environment and the people consuming tea. The study found that they release billions of micro-plastics (100 nanometers to 5 millimetres in size) and nanosized plastics (100 nanometers or smaller) into the tea.
Although these teabags are branded as 'silken', they are made out of nylon and polyethylene terephthalate (PET), a form of plastic that is found in water bottles. Some manufacturers use small amounts of plastic to reinforce their paper teabags as well.
The study was reported in the journal Environmental Science and Technology. The researchers steeped four different commercially available plastic teabags (with the actual tea removed) in water heated to 95°C (200°F). They used electron microscopes to analyze the contents of the water and teabags, concluding that an average of 11.6 billion micro-plastic and 3.1 billion nano-plastic particles had leached out of each bag into the water. This leaching happens because of heat.
The study states, the level of "particles released from the teabag packaging are several orders of magnitude higher than plastic loads previously reported in other foods".
Researcher Laura Hernandez says they were surprised by the amount released compared to those recorded in other studies into things like bottled water. This could be in part due to the fact they focused on the tiniest of particles - both microplastics, which are about the thickness of one hair, and nano plastics, which are a thousand times smaller.
But she also said it could be due to the fact "it's a piece of plastic being exposed to boiling water" and not just water at room temperature.
"There is really no need to package tea in plastic, which at the end of the day becomes single-use plastic," she said. "[And] which is contributing to you not just ingesting plastic but to the environmental burden of plastic."