New research from McGill University in Montreal, Canada, has found that some premium plastic tea bags can release billions of microscopic plastic particles into a single cup of tea. The study, published in the journal Environmental Science and Technology, examined four different commercial teas packaged in plastic mesh bags, often used for pyramid-shaped bags that producers claim improve infusion.
The researchers removed the tea leaves and heated the empty bags in water at 95°C, mimicking typical brewing conditions. They discovered that a single plastic tea bag released approximately 11.6 billion microplastic particles and 3.1 billion nanoplastic particles into the water. These particles are invisible to the naked eye and far exceed the levels of plastic contamination previously reported in other foods and beverages, such as bottled water.
Lead researcher Laura Hernandez expressed surprise at the high particle counts, attributing the difference partly to the focus on both microplastics (about the thickness of a hair) and nanoplastics (a thousand times smaller), as well as the exposure of plastic to boiling water. The study did not disclose the specific tea brands involved.
Hernandez advised consumers to avoid plastic packaging rather than specific brands, recommending loose-leaf teas or those packaged in paper tea bags. She highlighted that plastic tea bags become single-use plastic waste, contributing to both ingestion of plastic and environmental pollution. The World Health Organization has stated that microplastics in drinking water do not currently appear to pose a risk, but called for further research due to limited information.
