Chamomile, mint, rooibos, oh my! I love tea. Everyday tea. Tea to help calm my muscles. Tea to help me wake up. Tea to help my body detox. Tea tea tea.
OK I think you get the point.
Now I’m sure you won’t be surprised when I tell you that my heart broke when I recently learned that there exists a hidden danger in bagged tea. While I use loose tea on occasion, bagged tea is a teensy-bit more convenient, and so it’s what I typically grab at the grocery store. Though I am sure to choose organic tea so as to avoid pesticides, this may unfortunately be completely moot if the tea is bagged.
Plastic tea bags
Some newer teas have plastic bags, which are often pyramid-shaped and, I have to admit, are pretty darn cool looking. These are commonly made from food grade nylon or polyethylene terephthalate (PET), two of the safest polymers in terms of leaching potential. The Atlantic explains that though both also have very high melting points, there is another temperature point for plastics that needs to be considered: the “glass transition” temperature (Tg), the temperature at which the molecules of materials begin to break down. The Tg of a material is typically lower than its melting point. The Tg of PET is about 169°F, and the Tg of nylon is 116°F. Since water boils at 212°F, this is a major issue: the Tg of PET and nylon are exceeded.
“If the question is, ‘As the polymer goes through that transition state, is it easier for something to leach out?’ ‘the answer is yes,’ said Dr. Ray Fernando, professor and director of polymers and coatings at Cal Poly San Luis Obispo.”
Paper tea bags
If you’re like me, at this point you may be going, “Phew! Thank goodness I stay away from those fancy-pants pyramid tea bags.” But not so fast. To prevent paper tea bags from disintegrating or tearing, many are treated with epichlorohydrin, a compound mainly used in the production of epoxy resins that is considered a potential carcinogen by the National Institute for Occupational Safety and Health. Epichlorohydrin is also used as a pesticide.
When epichlorohydrin comes in contact with water, it “hydrolyzes” (science-speak for decompose) to 3-MCPD, a known carcinogen that has also been linked to in infertility and suppressed immune function. This is an issue considering that tea bags are intended to be completely submerged in water.
How can we protect ourselves?
For brewing loose tea, I have this stainless steel twisting tea ball, which is great for individual cups of tea. It is super convenient since you can just scoop the tea with the ball, close it up and plop it in your teacup!