Some premium tea bags leach billions of microplastics per cup: study

Researcher Nathalie Tufenkji says she now avoids tea bags containing plastics

A McGill University professor says tea lovers may be swallowing billions of tiny plastic particles along with their favourite brew.

Nathalie Tufenkji published a study Wednesday in the U.S. journal Environmental Science & Technology that examined the amount of microplastics and nanoplastics released when four unnamed brands of tea bags were steeped in hot water.

Researchers at the Montreal university focused their analysis on premium brands that come in voluminous, silk-like bags, instead of the more common paper variety.

“We were expecting to see some particles — obviously, just naturally from putting this material in hot water — but we were shocked when we saw that it’s actually releasing billions of particles from a single tea bag,” Tufenkji said Wednesday.

After emptying the bags of tea leaves, researchers submerged the bags in “ultra pure” water heated to 95 degrees Celcius for five minutes. When they analyzed a sample of the water, they found that a single plastic tea bag released approximately 11.6 billion microplastics and 3.1 billion nanoplastics into a single cup.

Tufenkji said that’s far higher than what other studies have found in other foods, for instance table salt, a kitchen staple that’s been reported as containing plastic. While 16 micrograms of microplastic was recorded in one cup of tea, table salt has been found to contain 0.005 micrograms per gram.

Tufenkji said the health risk of ingesting microplastics and nanoplastics is unknown and that her study only measured how much plastic was released by plastic tea bags.

She said a “very preliminary” toxicity study exposed water fleas to the steeping water, and researchers noted the tiny invertebrates behaved differently and appeared to have an altered body shape.

READ MORE: Humans unknowingly eat 100,000 particles of plastic per year, says new UVic study

As for human consumption, she stressed that there is no evidence of toxicity.

“We don’t know if it is dangerous,” she said.

“There’s actually almost no studies on the toxicity of ingesting microplastics or nanoplastics so that’s something to be determined, but we do know (some tea bags are) releasing a lot of plastic into the actual tea.”

The study also found that far fewer particles were released when the tea bag was steeped at room temperature for five minutes.

But that’s not the norm when brewing tea, the study acknowledges, adding that tea drinkers often heat water above the measured temperature of 95 °C and that even “food grade” plastics may degrade or leach toxic substances when heated above 40 °C.

Tufenkji said she now avoids tea bags containing plastics, but largely because of her aversion to single-use plastics.

“I do drink loose-leaf tea or tea in a paper tea bag,” said Tufenkji.

“I still continue to enjoy tea, that’s for sure.”

— By Cassandra Szklarski in Toronto

The Canadian Press

READ MORE: Organic Matters tea recalled across B.C. due to Salmonella

Like us on Facebook and follow us on Twitter

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

‘Perfect storm’ causes influx of black widows in the Okanagan

The region’s only venomous spider has come out in full force this year

Okanagan College expands ‘Wellness Wednesdays’ to all students this fall

Wellness Wednesday workshops are designed to be psycho-educational

AlleyCats Okanagan: Pet of the week

Mort is available through AlleyCats Alliance

Penticton film production seeking extras

Change of Pace is set to begin filming in Penticton Sept. 28

Veintimilla to run as Liberal candidate

The Oliver councillor will run for MLA of the Boundary-Similkameen riding

B.C. reports 96 new COVID-19 cases, one hospital outbreak

61 people in hospital as summer ends with election

Attorney General defends Kelowna Mountie involved in rough arrest

Tyler Russell filed a lawsuit against Const. Siggy Pietrzak in June of this year

‘Unprecedented’ coalition demands end to B.C. salmon farms

First Nations, commercial fishermen among group calling for action on Cohen recommendations

Earthquake off coast of Washington recorded at 4.1 magnitude

The quake was recorded at a depth of 10 kilometres

B.C.’s top doctor says she’s received abuse, death threats during COVID-19 response

Henry has become a national figure during her time leading B.C.’s response to the COVID-19 pandemic

Suspected human remains found in burned out vehicle on OKIB land

Vernon North Okanagan RCMP hand over investigation to Major Crimes

Kamloops RCMP search for armed robber of pizza restaurant

The incident unfolded on Monday evening at the Sahali Domino’s store

BC Liberals must change gears from election cynicism, focus on the issues: UBC professors

COVID-19 response and recovery is likely to dominate platforms

Trial underway for Kamloops man charged with kidnapping

Michael Mathieson is charged with armed robbery, unlawful confinement and kidnapping

Most Read