As Nathalie Tufenkji sat in a coffee shop about several years ago, a thought crossed her mind as she lowered a bag of tea into hot water.
Like so many tea bags these days, it was made of a plastic mesh. And Tufenkji, a PhD-level researcher and professor of chemical engineering at McGill University in Canada, couldn’t help but wonder — what’s happening to that plastic mesh as it soaks in hot water?
“She was having a cup of tea in a coffee shop when she realized the tea bag seemed to be made of plastic,” explains PhD student Laura Hernandez, first author of the study. “Then, she asked me to look into the possibility of this tea bag breaking down.”
After careful study, Tufenkji and Hernandez are finally able to share the answer with the world. And it puts a damper on a classic drink that brings health benefits and comfort to so many people around the world.
The findings? Steeping plastic tea bags in hot water results in billions of tiny pieces of plastic breaking off into the water.
Plastic Pieces in Tea: Main Takeaways
This isn’t McGill University’s first look at microplastics. “Our work with micro- and nanoplastics started when we looked into facial scrubs containing nanoplastics,” Hernandez explains. “In this work, we developed methods to find nanoplastics.”
Microbeads became popular as a cheaper replacement for exfoliators in facial scrubs and cleansers in the last decade. But with all of those tiny beads going down the drain, it spelled big trouble for our waterways, including the Great Lakes and beyond, where the plastics could build up in fish and damage ecosystems humans rely on.
Thankfully, microbeads in cosmetic products are now banned in the U.S., Canada and New Zealand.
But the tea bag study, published in the journal Environmental Science & Technology, is just the latest example of how plastic tends to break off in tiny bits. And how does that affects our health? Well, that’s still not clear, although some early indications are cause for concern.
But for the study, McGill researchers looked at four types of commercial teas packaged in plastic tea bags. To avoid any interference with the readings, they removed the tea from the bags and steeped the plastic bags in 95 degree Celsius water, which translates to about 200 degrees Fahrenheit.
And now, the stunning part …
“We show that steeping a single plastic teabag at brewing temperature releases approximately 11.6 billion microplastics and 3.1 billion nanoplastics into a single cup of the beverage.” — McGill University researchers
When it comes to microplastics, we’re talking about the same thickness of a single piece of hair; for nanoplastics, it’s 1,000 times smaller.
So while the benefits of green tea and many other teas are solid, we simply don’t know how drinking this amount of tiny plastics will impact us. When it comes to human health, we’re in uncharted territory here.
And just one last part of the study … Researchers also dosed a common small aquatic organism — a water flea — with the plastic-tainted water. While it didn’t outright kill them, they did show behavioral and anatomical abnormalities, Hernandez says.
Emerging Microplastic Pollution Concerns
Although investigating microplastic pollution is still considered a newer emerging area of science, researchers recently released some other concerning findings like:
- Microplastics are now detected in human feces.
- We use so much plastic, it’s now detected in the rain.
- Most plastics release estrogenic chemicals, a health threat linked to cancer and hormone imbalance. It’s well established that things like hot water, going through a cycle in the dishwasher, exposure to the sun and microwaving in plastic accelerate this unfortunate leeching.
- Microplastic accumulation could trigger inflammation, according to preliminary research.
- Certain microplastics may build up in organs, compromising the immune system and cell health.
- Inhaling microplastics can lead to poorer respiratory function and liver stress, according to animal studies.
- In past nanoparticle research, certain nanoparticles can cross the blood-brain barrier while also impacting the cardiovascular system while tampering with nutrient absorption and gut microflora and even reproduction.
- Other harmful chemicals can “hitchhike” on plastic and enter the human body.
What Should We Do About Plastic Pieces in Tea?
To be clear, the researchers want to stress the microplastic pollution detected in their study came from plastic tea bags, not the tea itself. “We would like the consumer to be conscious and evaluate the packaging that tea comes in. For instance, loose teas come without packaging, while other teas come in paper teabags. Single-use plastic packaging for teabags is not necessary.”
So thankfully, at least for this microplastic issue, there is an easy fix. If you drink a lot of tea, consider loose leaf tea and a food-grade stainless steel steeping ball. Or, just opt for tea in good old-fashioned paper bags. They’re great because you can remove the staple if there is one, along with the paper with that feel-good message at the end of the string and compost it.
Further, we just don’t know how ingesting microplastics fully effects humans in the long-term, but early research suggests one of our larger food exposures could be coming from shellfish.
But this study highlights the growing problem associated with single-use plastics — not just for the environment, but potentially human health, too.
- A first-of-its-kind study out of McGill University in Canada found steeping plastic tea bags in hot water releases billons of microscopic plastic particles into the beverage.
- Microplastics are about as wide as a piece of hair; nanoplastics are about 1,000 times smaller.
- The fix is easy when it comes to plastic in your tea: Avoid plastic mesh tea bags and use paper versions or loose leaf steeped in a stainless steel tea ball infuser.
- While we don’t fully know the effects of ingesting microplastics and nanoplastics, preliminary studies suggest it could trigger inflammation, hepatic stress, poorer respiratory function and immune system dysfunction.
- Start consciously reducing your single-use plastic. And don’t count on recycling, either … the recycling rate in the U.S. is just 9 percent.