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

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

RCMP. (Phil McLachlan/Capital News)
Suspect arrested after armed robbery in downtown Castlegar

Victim was allegedly threatened with knife and bear spray

Columbia Avenue Redevelopment — Phase 2 will begin in February. Image: City of Castlegar
Construction on the Columbia Avenue Redevelopment Project beginning March 1

Crews will be clearing brush and trees and removing asphalt

A dose of COVID-19 vaccine is prepared at a vaccination clinic in Montreal’s Olympic Stadium on Tuesday, Feb. 23, 2021. THE CANADIAN PRESS/Paul Chiasson
39 new cases of COVID-19 in Interior Health region

The total number of cases in the region since the pandemic began is now at 7,334

(file photo)
Nomination packages available for Castlegar byelection

The mayor’s seat and one council seat will be on the ballot

The Skinny Genes Foundation is raising awareness and funds for a rare genetic disorder that claimed both his father and uncle.
NHL players, local businesses help Kootenay man raise funds and awareness for rare genetic disease

Signed NHL jerseys and local business donations up for auction in Skinny Genes Foundation fundraiser

A health worker holds a vial of AstraZeneca vaccine to be administered to members of the police at a COVID-19 vaccination center in Mainz, Germany, Thursday, Feb. 25, 2021. The federal state of Rhineland-Palatinate, start with the vaccination of police officers in internal police vaccination centers. (Andreas Arnold/dpa via AP)
B.C. officials to unveil new details of COVID vaccination plan Monday

Seniors and health-care workers who haven’t gotten their shot are next on the list

An investigation is underway after a man was shot and killed by Tofino RCMP in Opitsaht. (Black Press Media file photo)
Man shot and killed by RCMP near Tofino, police watchdog investigating

Investigation underway by Independent Investigations Office of British Columbia.

Cannabis bought in British Columbia (Ashley Wadhwani/Black Press Media)
Is it time to start thinking about greener ways to package cannabis?

Packaging suppliers are still figuring eco-friendly and affordable packaging options that fit the mandates of Cannabis Regulations

B.C. Supreme Court in Vancouver on Tuesday December 11, 2018. THE CANADIAN PRESS/Darryl Dyck
B.C.’s compromise on in-person worship at three churches called ‘absolutely unacceptable’

Would allow outdoor services of 25 or less by Langley, Abbotsford and Chilliwack churches

Baldy Mountain Resort was shut down on Saturday after a fatal workplace accident. (Baldy Mountain picture)
Jasmine and Gwen Donaldson are part of the CAT team working to reduce stigma for marginalized groups in Campbell River. Photo by Marc Kitteringham, Campbell River Mirror
Jasmine’s story: Stigma can be the hardest hurdle for those overcoming addiction

Recovering B.C. addict says welcome, connection and community key for rebuilding after drug habit

A Vancouver restaurant owner was found guilty of violating B.C.’s Human Rights Code by discriminating against customers on the basis of their race. (Pixabay)
Vancouver restaurant owner ordered to pay $4,000 to customers after racist remark

Referring to patrons as ‘you Arabs’ constitutes discrimination under B.C.’s Human Rights Code, ruling deems

Nanaimo children’s author and illustrator Lindsay Ford’s latest book is ‘Science Girl.’ (Photo courtesy Lindsay Ford)
B.C. children’s writer encourages girls to pursue the sciences in new book

Lindsay Ford is holding a virtual launch for latest book, ‘Science Girl’

Most Read