Plastic and Cancerous Compounds in Tea Bags—A Surprising Source of Potential Toxins
April 24, 2013
By Dr. Mercola
I’ve long advocated drinking tea in lieu of coffee, but the downside of modern food technology is again rearing its ugly head and causing brand new health concerns over this otherwise healthful brew.
A recent article in The Atlantic1 raises questions about the safety of plastic tea bags, some of which have fancy pyramid shapes, designed to allow the tea leaves to unfurl during infusion.
Chances are you’ve never even given the tea bag a second thought. But indeed, some of the newer tea bags are made with a variety of plastics; some are nylon, some are made of viscose rayon, and others are made of thermoplastic, PVC or polypropylene.
Anyone aware of the dangers of plastic chemicals leaching out of plastic containers and bottles is likely to be concerned about drinking tea steeped through heated plastic.
The other bad news is that paper tea bags may be just as bad, or worse, than the plastic ones because many of them are treated with epichlorohydrin, a compound mainly used in the production of epoxy resins
Considered a potential carcinogen by the National Institute for Occupational Safety and Health2 (NIOSH), epichlorohydrin is also used as a pesticide. Besides making its way into tea bags, it can also be found in coffee filters, water filters, and sausage casings.
When epichlorohydrin comes in contact with water, it hydrolyzes to 3-MCPD, which has been shown to cause cancer in animals. It’s also been implicated in infertility (it has a spermatoxic effect in male rats3) and suppressed immune function4.
This chemical is already a well-known “process contaminant” associated with modern food production. According to the American Oil Chemicals Society5 (AOCS), 3-MCPD can also be found in variable levels in refined vegetable oils, which is yet another reason to avoid such cooking oils and replace them with organic coconut oil.
Do Plastic Tea Bags Pose a Health Concern?
As you probably know, chemicals in plastic containers and bottles have been found to leach into food and drink, thereby posing a number of health hazards. Examples include bisphenol-A (BPA), bisphenol-S (BPS), and phthalates, all of which mimic hormones and act as potent endocrine disruptors.
Unfortunately, according to the featured article, neither the Center for Health, Environment, and Justice nor the Center for Disease Control and Prevention (CDC) have any information on the toxicity of plastic tea bags or the levels of plastic chemicals that might migrate into the tea when steeped in hot water. Hard to believe, but true, the US federal agencies are not supervising this potential toxic exposure.
According to the featured article:
“Could plastic tea bags also be bad for our health? They are most commonly made from food grade nylon or polyethylene terephthalate (PET), which are two of the safest plastics on the scale of harmful leaching potential.
Both have very high melting points, which offer some assurance to consumers, as one would think the melting point of plastic is the temperature at which one would need to worry about accidentally eating it.
There is another temperature point for plastics, though, that we may need to worry about, called the ‘glass transition’ temperature (Tg) . That is the temperature at which the molecule in certain materials such as polymers begin to break down. As a rule, the Tg of a material is always lower than the melting point.“
Water boils at 212 degrees Fahrenheit (100 degrees Celsius). In the case of PET the glass transition point (Tg) is about 169 degrees, and the breakdown point of nylon is even lower than PET.
“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,” The Atlantic states.
So while these plastics are generally considered among the safest in terms of leaching potential, the molecules in these plastic tea bags may still in fact break down and leach out when steeped in boiling water—which is the recommended way to brew a good cup of tea, especially when you’re using higher quality whole tea leaves, which these newer tea bags are designed for…
Paper Tea Bags May Be Just as Bad, or Worse…
The now defunct Dexter Corporation was the initial owner on the patent6 of a method for treating both tea bags and coffee filters with latex (plastic), to aid in preventing tears that allow the tea leaves/coffee grounds to leak. This invention “saturates and completely impregnates” the entire web material. Therein lies one of the problems with paper tea bags as they are frequently treated with epichlorophydrin, which hydrolyzes to the carcinogen 3-MCPD when contact with water occurs.
Dow Chemical Co is one of the largest producers of epichlorophydrin. According to safety literature7 from Dow, it’s a very dangerous chemical that requires using extra precautions when handling. Granted, that doesn’t automatically render it dangerous in the final product, but it can still be a cause for concern, particularly as it can turn into a carcinogen when water is added. There are many unanswered questions with respect to the potential hazards of using this chemical in products specifically designed to be used with boiling water…
A good way to protect yourself and your family in this area is to purchase your tea from manufacturers who can certify that their tea bags do not contain this compound. Organic India, for example, has sent me a confirmation that the paper used for their tea bags does not contain epichlorohydrin. In a 2009 article, Kristie Leong, MD also claims to have done her own inquiries and that Bigelow Tea Company does not use the chemical in their bags8. Many plastic tea bags are advertised as “silky” or “mesh bags,” or they’ll have fancy shapes or oversized bags. I’d suggest avoiding those as well if you want to be on the safe side.
Your best option would be to opt for loose tea. This does take longer, but it can be well worth the wait. One of my favorite teas is Royal Matcha Green Tea, which has one of the highest levels of the potent antioxidant epigallocatechin gallate (EGCG). Unlike other teas which you steep and strain, matcha tea is a powder made from ground green tea leaves. You add the powder right into the water. You are consuming the whole leaf, which makes matcha one of the healthiest green teas available. Another excellent option is loose Tulsi tea leaves. This well-known Ayurvedic herb is also full of antioxidants that fight free radicals in your body and prevent oxidation damage.
How to Brew the Perfect Cup of Tea
There is an art to brewing tea using loose tea leaves, but once you find your “sweet spot” you may never go back to bagged tea again. Here are a few simple guidelines for making the “perfect” cup of tea:
Bring water to a boil in a tea kettle (avoid using a non-stick pot, as they too can release harmful chemicals when heated)
Preheat your tea pot or cup to prevent the water from cooling too quickly when transferred. Simply add a small amount of boiling water to the pot or tea cup that you’re going to steep the tea in. Ceramic and porcelain retain heat well. Then cover the pot or cup with a lid. Add a tea cozy if you have one, or drape with a towel. Let stand until warm, then pour out the water
Put the tea into an infuser, strainer, or add loose into the tea pot. Steeping without an infuser or strainer will produce a more flavorful tea. Start with one heaped teaspoon per cup of tea, or follow the instructions on the tea package. The robustness of the flavor can be tweaked by using more or less tea
Add boiling water. Use the correct amount for the amount of tea you added (i.e. for four teaspoons of tea, add four cups of water).
The ideal water temperature varies based on the type of tea being steeped:
White or green teas (full leaf): Well below boiling (170-185 F or 76-85 C). Once the water has been brought to a boil, remove from heat and let the water cool for about 30 seconds for white tea and 60 seconds for green tea before pouring it over the leaves
Oolongs (full leaf): 185-210 F or 85-98 C
Black teas (full leaf) and Pu-erhs: Full rolling boil (212 F or 100 C)
Cover the pot with a cozy and let steep. Follow steeping instructions on the package. If there are none, here are some general steeping guidelines. Taste frequently as you want it to be flavorful but not bitter:
Oolong teas: 4-7 minutes
Black teas: 3-5 minutes
Green teas: 2-3 minutes
Once desired flavor has been achieved you need to remove the strainer or infuser. If using loose leaves, pour the tea through a strainer into your cup and any leftover into another vessel (cover with a cozy to retain heat)
After Water, Tea is One of Your Healthiest Beverage Choices
While some tea bags—whether plastic or paper processed with epichlorophydrin—may pose a potential hazard, please don’t let that deter you from drinking tea altogether. Although I still believe pure water should make up the majority of your daily fluid intake, high-quality tea has numerous health benefits to offer. Among them is growing evidence that the polyphenols in tea, which include EGCG (epigallocatechin gallate) and many others, can be protective against cancer. For example, the polyphenols in green tea appear to be even more effective at fighting the progression of cancer than the antioxidants found in red wine and grapes.
Beyond this, the beneficial properties in tea have been known to:
Neutralize the effects to your body of harmful fats and oils
Inhibit bacteria and viruses
Protect against oxidation in your brain and liver
Help promote healthy gums
Drinking tea has also been linked to:
Improved mental alertness and slowing of brain-cell degeneration
Reduced blood pressure
Protection again type 2 diabetes
Lower blood cholesterol and triglyceride levels
Lower risk of breast, colon, lung, ovarian and prostate cancers
Reduced risk of heart attack and stroke
Of course, there are some general ground rules to follow when selecting tea of any kind, and those are that it should preferably be:
Organic (otherwise tea may be heavily sprayed with pesticides)
Grown in a pristine environment (tea is known to accumulate fluoride, heavy metals and other toxins from soil and water, so a clean growing environment is essential to producing a pure, high-quality tea)
So keep these tips in mind, and go ahead and enjoy a cup or two of your favorite variety. I personally prefer Matcha tea, a vibrant bright green tea made of tea leaves ground into a powder, and Tulsi tea, which is a powerful adaptogenic herb that provides important therapeutic benefits.