Plastic teabags are releasing billions of microplastics into cups of tea, according to research.
Researchers at McGill University in Canada found a plastic teabag, typically produced in a pyramid shape for upmarket teas, released about 11.6bn microplastic and 3.1bn nanoplastic particles into the water.
The team explored the effects of the particles on water fleas. “Although the animals survived, they did show some anatomical and behavioural abnormalities,” said the university.
Nathalie Tufenkji, a professor of chemical engineering at McGill, said in an interview with CBC News that the particles were the size of grains of dust or pollen. She said the water fleas swam “crazily” and their carapaces “ballooned”.
The university said: “While the possible health effects of ingesting these particles are currently unknown, the new research… suggests further investigation is needed.”
In the research the scientists took four different commercial teas packaged in plastic teabags, cut them open and then heated bags in water to simulate brewing tea. They then used an electron microscope to measure the plastic released. Uncut bags were also tested to ensure the cutting process was not producing the particles.
Separately, a study carried out by Newcastle University has found delicate wash cycles release more plastic microfibres than other cycles.
Researchers found delicate cycles used more water than others and as a result released 800,000 more fibres.
PhD student Max Kelly, who led the research, said: “This is because the high volume of water used in a delicate cycle, which is supposed to protect sensitive clothing from damage, actually plucks away more fibres from the material.”
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