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

Hope-raised NHL official among BC Hockey Hall of Fame inductees

Jay Sharrers officiated 1,419 regular NHL games, plus Stanley Cup finals and Olympics

How would crowded Fraser Valley hospitals deal with patient surge? Officials won’t say

Amid coronavirus case and crowding issues, health officials won’t say where more patients would go

Sasquatch Mountain Aussie Day celebration raises $800

Proceeds of bikini runs, toonie tosses and more go to wildfire victims

Artists at Work featured at Hope Arts Gallery in February

Melange 2020 will showcase myriad talents by local artists until Feb. 28

DNA confirms SUV struck and killed Abbotsford cyclist in 2015, court hears

Kerry Froese operated company that owned vehicle that struck and killed Ronald James Scott in 2015

VIDEO: Feds look to help 126 Canadians quarantined in China for coronavirus

China has confirmed more than 4,500 cases of the new virus, with more than 100 deaths

Party bus door fault for years ahead of Langley woman’s death: Coroner

Tuesday report classifed Chelsea James’ death accidental, but was critical of bus inspection process

Sap thief taps Saanich park maple trees, faces hefty fine

One tree found with four taps in Mount Doug Park

B.C. reports first coronavirus in Vancouver region

First patient visited Wuhan, China, reported symptoms

Uber threatens legal action to ‘defend its right’ to operate in Surrey

‘I have no concerns,’ Mayor Doug McCallum replies

Victoria resident says WestJet employee uttered racist comment, refused to let her on plane

Customer claims she was told ‘You guys can’t handle your alcohol’ by WestJet employee

Bystander who tried to help dog being attacked not liable for its death: B.C. tribunal

Owner of dog killed tried to get $5,000 in damages from man who tried to save it

INFOGRAPHIC: See how fast your B.C. city grew in 2019

The province’s fastest-growing municipalities were located on Vancouver Island

Landowner hearings begin for Trans Mountain expansion in Alberta

Detailed route talks start in Spruce Grove, in B.C. communities soon

Most Read