New research from McGill University in Canada has revealed that some plastic tea bags shed billions of microscopic plastic particles into hot water during brewing. The study, published in the journal Environmental Science and Technology, found that a single plastic tea bag can release approximately 11.6 billion microplastic and 3.1 billion nanoplastic particles into water heated to 95°C.
The researchers tested four different commercial teas packaged in plastic mesh bags, often used by premium brands to create a pyramid shape. They removed the tea leaves and steeped the empty bags in hot water, finding particle levels “several orders of magnitude higher than plastic loads previously reported in other foods.”
Lead researcher Laura Hernandez expressed surprise at the high levels, noting that the combination of plastic packaging and boiling water may contribute to the release. The study did not disclose specific tea brands, but Hernandez advised consumers to avoid plastic packaging altogether and opt for loose tea or paper tea bags.
The World Health Organization has stated that microplastics in drinking water do not appear to pose a risk based on current evidence, but it called for more research. The McGill team echoed this call, emphasizing the need to investigate potential health effects of ingesting microplastics and nanoplastics.
