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Grocery store-bought tea bags release billions of microplastic particles into every cup
Those silky tea bags might be releasing plastics into your digestive system.

- A new study at McGill University discovered that many tea bags leach billions of plastic particles into every cup.
- While the health dangers are unknown, past research uncovered serious problems in other mammals when consuming such particles.
- Scientists estimate that between five and 13 million metric tons of plastic are dumped into oceans every single year.
When I initially shared a new study from McGill University that found plastic tea bags release billions of microplastics and nanoplastics on social media, most commenters asked, "Who drinks from plastic tea bags?" Many of us do, it turns out.
Discovering which companies use plastic tea bags takes some work, but the story isn't exactly new. In 2013, The Atlantic reported on an increasing amount of tea manufacturers placing their leaves in "silky" or "mesh" tea bags. What appeared to be an evolution of the standard Lipton's approach — you could see and smell the leaves — turns out to be potentially damaging to our health.
That's what Nathalie Tufenkji, a professor of chemical engineering at McGill, thought one day when ordering a cup of tea at a Montreal café. Along with fellow researchers, she tested out four different tea bags constructed of plastic in her laboratory. The team discovered that, when brewed to 95 degrees Celsius, these bags release 11.6 billion microplastics and 3.1 billion nanoplastic particles into each cup.
Their findings were published in the journal Environmental Science & Technology on Sept. 25.
Some tea bags may shed billions of microplastics per cup
We know the damage that climate change is having on oceans — yet another report, this one issued by the United Nations, highlights how dangerously close we are to destroying ecosystems that most biological life on the planet depends on.
Plastic is also a pervasive problem in our world: since the '50s, humans have produced over 8.3 billion metric tons of plastic, with roughly half of it being made over the last 15 years. Scientists estimate that between five and 13 million metric tons of plastic are dumped into oceans every single year. Warming temperatures and plastic particles create a perfect storm in the destruction of entire ocean habitats.
That's not the only place plastics show up, the McGill team writes. Microplastics have been discovered in table salt, fish, and water — from taps, but even more so from plastic water bottles. They're also being used in facial scrubs and toothpaste, along with, of course, drinking straws. In cafés around Los Angeles, I constantly witness cold brew coffee being served in plastic cups with plastic lids, sipped through with plastic straws that are delivered wrapped in plastic. I'm sure this practice is not limited to this city.
As the comedian, George Carlin, famously noted, maybe the purpose of humans was to put plastic on the planet. Given the data, his hypothesis may turn out to be correct.
Back to the McGill study, researchers steeped empty plastic teabags in reverse osmosis water for five minutes at 95 degrees Celsius. They then scanned the water using electron microscopy, confirming particle composition using two other forms of spectroscopy. The four brands used were all sourced from grocery stores and coffee shops in Montreal.
Photo by Zikri Maulana/SOPA Images/LightRocket via Getty Images
As of now, the health impact of consuming plastic particles is unknown in humans. Previous studies have confirmed environmental and health effects in populations of algae, zooplankton, fish, and mice. Numerous studies involving the mammalian gut (in rodents, rabbits, and dogs) show that plastic particles are translocated in the body once inside of the digestive tract. The team writes,
"Potential biological responses include genotoxicity, apoptosis, and necrosis, which could lead to tissue damage, fibrosis and carcinogenesis."
As Taylor Orci wrote in The Atlantic in 2013, tea companies emphasize the quality of tea over the fact that you're drinking plastic. Best to disguise the fact that these particles are being leached into consumer's cups. That some companies advertise plastic-free teabags is telling of an industry-wide issue.
We'll need more research to uncover the actual health effects of drinking these particles — between 2013 and 2019, no one has measured the harm of these substances, making you wonder what the FDA and CDC are doing. Regardless, it's hard to square the benefits of green tea when you're enjoying it with a side of plastic.
Image source: Nathalie Tufenkji et al. McGill University.
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Listen: Scientists re-create voice of 3,000-year-old Egyptian mummy
Scientists used CT scanning and 3D-printing technology to re-create the voice of Nesyamun, an ancient Egyptian priest.
- Scientists printed a 3D replica of the vocal tract of Nesyamun, an Egyptian priest whose mummified corpse has been on display in the UK for two centuries.
- With the help of an electronic device, the reproduced voice is able to "speak" a vowel noise.
- The team behind the "Voices of the Past" project suggest reproducing ancient voices could make museum experiences more dynamic.
Howard et al.
<p style="margin-left: 20px;">"While this approach has wide implications for heritage management/museum display, its relevance conforms exactly to the ancient Egyptians' fundamental belief that 'to speak the name of the dead is to make them live again'," they wrote in a <a href="https://www.nature.com/articles/s41598-019-56316-y#Fig3" target="_blank">paper</a> published in Nature Scientific Reports. "Given Nesyamun's stated desire to have his voice heard in the afterlife in order to live forever, the fulfilment of his beliefs through the synthesis of his vocal function allows us to make direct contact with ancient Egypt by listening to a sound from a vocal tract that has not been heard for over 3000 years, preserved through mummification and now restored through this new technique."</p>Connecting modern people with history
<p>It's not the first time scientists have "re-created" an ancient human's voice. In 2016, for example, Italian researchers used software to <a href="https://www.smithsonianmag.com/smart-news/hear-recreated-voice-otzi-iceman-180960570/" target="_blank">reconstruct the voice of Ötzi,</a> an iceman who was discovered in 1991 and is thought to have died more than 5,000 years ago. But the "Voices of the Past" project is different, the researchers note, because Nesyamun's mummified corpse is especially well preserved.</p><p style="margin-left: 20px;">"It was particularly suited, given its age and preservation [of its soft tissues], which is unusual," Howard told <em><a href="https://www.livescience.com/amp/ancient-egypt-mummy-voice-reconstructed.html" target="_blank">Live Science</a>.</em></p><p>As to whether Nesyamun's reconstructed voice will ever be able to speak complete sentences, Howard told <em><a href="https://abcnews.go.com/Weird/wireStory/ancient-voice-scientists-recreate-sound-egyptian-mummy-68482015" target="_blank">The Associated Press</a>, </em>that it's "something that is being worked on, so it will be possible one day."</p><p>John Schofield, an archaeologist at the University of York, said that reproducing voices from history can make museum experiences "more multidimensional."</p><p style="margin-left: 20px;">"There is nothing more personal than someone's voice," he told <em>The Associated Press.</em> "So we think that hearing a voice from so long ago will be an unforgettable experience, making heritage places like Karnak, Nesyamun's temple, come alive."</p>Virus made inequality much worse across the world, says report
Inequality in wealth, gender, and race grew to unprecedented levels across the world, according to OxFam report.
A businessman walks by a woman asking for money in New York City.
- A new report by global poverty nonprofit OxFam finds inequality has increased in every country in the world.
- The alarming trend is made worse by the coronavirus pandemic, which strained most systems and governments.
- The gap in wealth, race and gender treatment will increase until governments step in with changes.
People wait in line to receive food at a food bank on April 28, 2020 in Brooklyn.
Photo by Spencer Platt/Getty Images
Credit: Oxfam International
Scientists find 'smoking gun' proof of a recent supernova near Earth
A supernova exploded near Earth about 2.5 million years ago, possibly causing an extinction event.
An artist's impression of a supernova.
- Researchers from the University of Munich find evidence of a supernova near Earth.
- A star exploded close to our planet about 2.5 million years ago.
- The scientists deduced this by finding unusual concentrations of isotopes, created by a supernova.
This Manganese crust started to form about 20 million years ago. Growing layer by layer, it resulted in minerals precipitated out of seawater. The presence of elevated concentrations of 60 Fe and 56 Mn in layers from 2.5 million years ago hints at a nearby supernova explosion around that time.
Credit: Dominik Koll/ TUM
I spoke to 99 big thinkers about what our ‘world after coronavirus’ might look like – this is what I learned
There is no going "back to normal."
