- Researchers say tea in plastic bags can release billions of microplastics into a warm cup of tea.
- They add that paper tea bags don’t contain microplastics.
- Experts say the microplastics probably don’t pose serious danger to tea drinkers.
Your morning cup of tea can provide warmth and a much-needed dose of caffeine.
But a new study may make your most savored beverage tough to swallow.
If you’re using a plastic tea bag, you could be pouring microplastics and nanoplastics into your cup.
Researchers at McGill University in Montreal, Canada, report that a single plastic tea bag releases 11 billion micro-sized plastic particles and 3 billion nano-sized plastic particles into 95-degree water.
Before you begin a mass exodus of Earl Grey from the cupboard, there are some important things to know about this study and its findings.
First, all tea bags are not created equal and not all cups of tea will be filled with billions of plastic particles. If your tea bags are made of paper, keep calm and carry on.
Laura Hernandez, a PhD student at McGill and the first author of the study, noted there are paper tea bags and plastic tea bags.
The four different types of tea bags used in the study were purchased at cafes and stores in Montreal.
“The plastic kind are typically pyramid shaped, but not always,” she told Healthline.
The researchers simulated brewing with empty plastic teabags.
They removed the tea because it contains oil that would have made it impossible to view the plastics later.
After they steeped the tea bags, the researchers analyzed them with an electron microscope and were blown away by what they saw.
“We were expecting to find a few plastic particles, maybe hundreds or thousands,” Hernandez said. “But we were extremely surprised to find billions of particles. Billions of plastics came out of the tea bag.”
Hernandez describes microplastic as around the size of a human hair in terms of thickness.
“Nanoplastic is 1,000 times smaller,” she said. “To observe this very small plastic, we had to use very specialized equipment. They aren’t visible to the naked eye.”
The levels of plastic discovered were thousands of times higher than those reported previously in other foods.
Studies have shown approximately 0.005 micrograms of plastic per gram of table salt, “whereas in one cup of tea, you’re drinking 16 micrograms of plastic,” Hernandez noted.
The scientists took their research one step further by seeing what effect the plastics would have on small aquatic organisms called Daphnia magna, also known as water fleas, that ingested the tiny plastics.
“What we observed is that the structure that covers their body was deformed,” she said. “We also observed that they had altered swimming behavior.”
So what does all this mean for people who are all about their oolong?
The findings don’t necessarily prove that tea drinkers are in any grave danger.
“Currently there’s no scientific evidence that plastics are harmful or not harmful to human beings,” Hernandez said. “We are ingesting them not only in tea but in many other ways. We as scientists call on other scientists, such as toxicologists and medical doctors, to look into this to see what the effects of plastic would be on human health.”
Lisa Y. Lefferts, MSPH, senior scientist at the Center for Science in the Public Interest in Washington, DC, agreed that the impact of plastics on human health isn’t known.
She added that possible risks from these types of plastics are thought to depend on a number of factors, “such as size, shape, surface area, composition, whether pathogens or other chemicals are attached, and the dose or amount.”
She noted it’s important to avoid possible risks. In this case, it’s easy to do so by not choosing plastic tea bags.
“As an avid tea drinker, I will avoid plastic tea bags and stick to paper tea bags or loose-leaf tea,” Lefferts told Healthline. “Meanwhile, I think it’s important to not lose sight of risks we do know about. For example, if you smoke, text while driving, or drink alcohol excessively, I think it makes more sense to focus on those large known risks before worrying about microplastics in your tea.”
Hernandez, a chemical engineering student and tea lover, doesn’t want to rain on anybody’s tea party. She recommends using this information to make informed decisions going forward.
“Be observant of the type of packaging your tea comes in,” she said. “The plastic packaging isn’t necessary.”
Not all companies list on the label if their tea bags are plastic or paper, so watch for plastic tea bags that are transparent or marketed as “silky,” Hernandez said.
“If you can see the tea inside, it’s most likely plastic,” she said.