In previous articles here, here and here, I wrote about the dangers of an environmental toxin called bisphenol-A (BPA). BPA is a chemical that is found in several plastics and plastic additives. It’s in the water bottles some folks carry to gyms, the canned tomatoes and coconut milk they cook with, and in the baby bottles moms use to feed their infants.
We’ve known for decades that BPA has estrogenic activity. In vivo animal studies and in vitro cell-culture research has linked low-level estrogenic activity associated with BPA exposure to all kinds of fun stuff, like diabetes, ADHD, heart disease, infertility and cancer.
There is now significant evidence suggesting that even low levels of BPA-exposure can cause harm, and this is particularly true in vulnerable populations like pregnant women, infants and the chronically ill. (1)
Because of this research, and the growing public awareness that BPA should be avoided, a new crop of “BPA-free” plastic food containers and baby bottles has been introduced. However, a recent study published in the journal Environmental Health Perspectives in July has shown that even BPA-free plastics have chemicals with estrogenic activity (EA), and can cause serious health problems as a result. (2)
What is “estrogenic activity” (EA)?
Chemicals with estrogenic activity (EA) are those that mimic or antagonize the actions of naturally occurring estrogens. These chemicals are capable of binding with one or more of the nuclear estrogen receptors in the body.
The best way to think of chemicals with EA is as a counterfeit key fitting into a loose lock.
As I mentioned above, vulnerable populations such as pregnant women, developing fetuses, infants and children are especially sensitive to even very low doses of chemicals with EA. (4)
BPA-free is not EA-free
In the Environmental Health Perspectives study, Yaniger et al. set out to determine the estrogenic activity of commonly used plastic consumer products.
They bought more than 500 plastic products at places like Wal-Mart, Whole Foods, Trader Joe’s, Target, and other major retailers. They selected from all categories of plastic, including tupperware containers, bags and wraps.
Then they cut the containers into pieces, put them into liquids that contain similar chemicals found in food and drinks, and subjected them to stresses that mimic normal use, like UV light (sunlight), microwaving, or moist heat (like boiling or dishwashing).
Their results showed that over 90 percent of the products leached estrogenic chemicals before they were even stressed, and after being stressed essentially all of the products showed estrogenic activity.
According to Stuart Yaniger, one of the lead authors of the study:
Baby bottles, plastic bags, plastic wrap, clamshell food containers, stand-up pouches: Just about anything you can think of that’s made of plastic that food or beverages are wrapped up in, we found this activity. It was shocking to us.
What plastics do and don’t have EA? It’s impossible to tell.
The exact chemical composition of most plastic products is proprietary and thus not known, and a single plastic item containing many parts (e.g. a baby bottle) may consist of >100 chemicals, all of which can leach from the product.
In light of the researchers’ finding that nearly all of the 500 plastic products they tested leached when stressed, and 90 percent of them leached even without stress, I think it’s pretty safe to assume that most plastic products you can buy in the store have chemicals with EA.
It’s important to reiterate that this is true even with BPA-free plastics. In fact, the Environmental Health Perspectives study found that some BPA-free products had even more EA than BPA-containing products!
Should you be concerned about chemicals with EA?
There are still a lot of unknowns in the discussion of the EA of various chemicals in plastic products, such as the number of chemicals having EA, their relative EA, their release rate under different conditions, and their half-lives in human beings of different ages.
However, there are 3 strong arguments for being “better safe than sorry” when it comes to plastics and EA (5):
- in vitro data overwhelmingly show that exposures to chemicals with EA (even in very low doses) change the structure and function of human cell types;
- many studies present clear cellular, molecular and systemic mechanisms by which chemicals having EA produce changes in cells, organs and behaviors; and,
- recent epidemiological studies strongly suggest that chemicals with EA produce measurable changes in the health of various human populations.
Perhaps the study authors summed it up best in their conclusion:
Many scientists believe that it is not appropriate to bet our health and that of future generations on an assumption that known cellular effects of chemicals having EA released from most plastics will have no severe adverse health effects.
I couldn’t agree more.
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What you can do to reduce your exposure to chemicals with EA
Here’s a list of things you can do to reduce your exposure – and especially your baby’s and children’s exposure – to chemicals with EA.
- Use glass containers and canning jars at home for food storage. Be aware that the lids of Mason and Kerr brand canning jars contain BPA and chemicals with EA. There are BPA-free lids, but they still may contain chemicals with EA, and I’ve been told they’re made with formaldehyde. Weck makes 100% glass jars that are a good alternative. Crate and Barrel sells them here.
- Use stainless steel containers in the freezer instead of freezer bags.
- Use a stainless steel water bottle (like the Klean Kanteen) instead of plastic bottles.
- Don’t drink bottled water from plastic bottles, especially when they’ve been exposed to sunlight.
- Parents: use glass baby bottles instead of plastic. Evenflo is a commonly available brand you can buy at Target, Wal-Mart, Walgreens, Rite-Aid, etc. and online at Amazon and other retailers.
Special note for Sous Vide users: After reading this study, I’m feeling very uncomfortable about the idea of eating anything that comes out of a plastic bag that has been sitting in a hot water bath for several hours. This is a crushing blow, as I love cooking with the Sous Vide. But in light of the evidence that even BPA-free plastics bags leach chemicals with EA even without added stress like a hot water bath, I think erring on the side of caution is probably wise.
UPDATE 10-28-11: make sure to read the comments section for some good recommendations.
UPDATE 11-7-11: check out this article on Nom Nom Paleo, one of my favorite Paleo food blogs. She did some homework and found some information claiming that re-usable silicon bags don’t have EA chemicals. However, Stuart Yaniger, one of the authors of the paper I referenced in this article, commented on her post (and below) that most silicon products do, in fact, leach EA chemicals. I’m also wary of the claim that FoodSaver bags don’t have any EA without 3rd party, independent testing. As Yaniger’s article demonstrated, we should assume all plastics have EA until proven otherwise.
Resources for those who want to avoid plastic entirely
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Thanks for the detailed research! I looked around and found some (expensive) all-cloth lunch and snack bags for my daughter’s school lunches. Some of them are lined with nylon, are there any data about leaching from nylon?
Here’s a few references. Once you get past the jargon, they’re pretty straightforward:
http://oehha.ca.gov/multimedia/biomon/pdf/1208cyclosiloxanes.pdf
Horii and Kannan, Archives of Environmental Contamination and Toxicology
Volume 55, Number 4, 701-710, DOI: 10.1007/s00244-008-9172-z
Anne Quinn et al, Toxicol Sci. 2007 Mar;96(1):145-53
These should be available at nearly any good university library.
Wow! I did not expect an answer that fast! Thank you VERY much for the information, Mr. Yaniger; I appreciate it and will keep digging!
Thank you for the well written article! I have already started eliminating plastics from my kitchen months ago. (In fact, my cats were plastic free YEARS before due to feline acne. You think that would have been a clue for me!)
However, the comment by Mr. Yaniger that even medical grade silcone can leach EA is a little frightening to me because I use a menstrual cup (Diva), and I’m worried that it could be just one more thing keeping me infertile. I’ve done a quick search online to find out which types of silicone can leach EA, but haven’t found anything definite one way or the other (no true references – just comments that solid medical grade silicone doesn’t leach things in the body from websites selling the cup or other comments mentioning statements from this very page). I would appreciate it anyone could point me to some studies on this topic!
Other than that, I look forward to reading through the archive of posts! Thank you!
Heather, there’s not much published data (I think we had a few mentions in our EHP paper), and certainly no published data on which brands are safe and which aren’t. Medical grade is no guarantee- the levels at which EA is detectable and possibly biologically significant are much lower than the FDA limit on total migrant.
Dow-Corning did some work a few years ago on the EA of two common contaminants. I’ll see if I can dig up the reference for you.
Seems like comments have tapered off a bit, but I thought I would add my thoughts. As a first step, I am no longer heating foood in any plastic containers, like ziplock and glad food storage. I used to have an ancient set of glass food storage containers made specifically for the refrigerator, but they all broke over time. At this point I am far more concerned with the interaction of glass and ceramic tile under the influence of gravity. I have had bad gashes in my feet over the years from glass on beaches, and things that broke alongside my pool. In fact we have a rule no glass in the yard. So, I invested in some melamine and lexan type polycarbonate stemware for outdoor use. I am not going to stop using those but do not heat food in them anyway. The bigger issue is that most produce from my CSA comes in poly bags. As does grocery store stuff. And trader joes puts everything in plastic. I send my husband to work every day with two meals. Most of the protein is pre cooked and just needs heating so I guess he can empty his baggies onto paper plates and keep some tableware in his drawer. It is absolutely unfeasable to carry two meals a day in glass and metal is not suitable for reheating in. It’s a real challenge, also since he totes his water to work. So we have decided to start with the most obvious exposure, not reuse any sour cream or yogurt containers, not heat in plastic and not store leftovers or planned overs in plastic. Other than that, I cannot see what else to do. I already pitched all my Tupperware that I had all my grains in, when the contents hot expunged. But all our nuts, seeds, dry fruit is in plastic. Clearly one can get obsessed or one can use common sense.
I have used Evenflo glass bottles for my 4yo and 2yo and have been very pleased. I did breastfeed them 13 months and 22 months, but supplemented with pumped milk and even pumped right into the Evenflo bottles with a Medela pump. I am the only one to ever break one, by dropping them in the kitchen. I used the silicone sleeves on the outside, and some padded plastic water bottle covers that also fit the 8-oz Evenflo bottles. I used both the 8 and 4-oz bottles. We still use them, since I don’t want to use the plastic sippy-type cups when they aren’t using a regular glass or cup.
Two persons mentioned that they use a Brita plastic water filter; anybody has suggestions about that?
I also use one at home and I’ve been looking for alternatives but didn’t find any. I think Brita filters are BPA-Free, but from what I know now seems unlikely that they are EA free. Your help would be greatly appreciated 🙂
I use Soma Water It’s glass so the water isn’t sitting in plastic at least.
https://www.drinksoma.com/
Hi Chris,
Our office has been drinking water from the Arrowhead 3 gal. water dispenser for over 15years. In trying to eliminate BPA exposure, I look for the #7 on the plastic container. Much to my disappointment, I went to pour a glass of water today and saw a #7 on the plastic jug on top of the dispenser. I wrote Arrowhead and decided to follow up with a phone call today. I spoke with a customer service rep initially who told me they are aware of this issue and are in the process of converting #7 containers to #1. When I asked when I might get a #1 container to my office, she could not answer that and transferred me up to a higher authority. The woman I next spoke with, said that they are aware that their container does have a very small trace amount of BPA in it (comparable to 1:1Billion) and that the BPA does not leak into the water. I told her that was contrary to everything I had been reading about BPA leaking into food and liquids. She held firm and I suggested she e-mail the research and resources that support her assertion. She will be emailing me that information tomorrow. I emphasized that California along with 10 other states will be banning BPA from baby bottles/feeding containers the concern is so prevalent. She began to say that the baby bottles in the news are of a higher BPA. She also could not tell me when (if they are in fact in the process of converting to #1) that I could get my #7 bottles exchanged out. She also said (contrary to the previous rep) that they were not converting the bottles to #1 due to the BPA issue but that they were converting it to #1 as an easier recycling option.I wanted to share this with you to see what you thought/call on a higher health power to possibly analyze this. What do you think? In the meantime, I will be transporting my water from home in a stainless steel container. Thanks, Chris!
How would one check to see if exposure to chemicals with EA is too high? I recently did a hormonal test and found my testosterone to be at an optimal level. Would excessive exposure to chemicals with EA manifest itself as depressed testosterone, elevated estrogen, or something else measurable?
Diethylhexyl phthalate (aka dioctyl phthalate) is everywhere, in much larger quantities than BPA. For example, in all of the power cords and network cables on our computers. Fortunately, it isn’t as potent as BPA, but the exposures may be larger. When I was a kid, chew toys were made out of it. I think that it would bear mention in this article.
what is good to microwave in then? What about pyrex glass and the like, it’s not totally clear, but wikipedia says pyrex can be anywhere from 38 to 80% silicone, can this be a problem in this form?
Glass does not contain silicone- it does have silicon (a very different thing). If it’s microwave safe, I’d go for it. If there’s any question about microwave safety of a glass container, microwave it empty for 30 seconds or so. If it gets very hot, you probably shouldn’t use it.
Do this also apply for storing food in plastic container (already cold) as well? I never microwave anything in plastic container and always waited the food to cool down completely before storing them in plastic containers.
I have a water purification system under my sink, all the pipes are plastic, the filter housings are plastic, and the holding tank is metal with plastic lining. I called a company that sells them and he said they are all like that, you are basically drinking out of a plastic bottle. I thought about getting an ionizer, but they are plastic coated on the inside. Seems ridiculous that for over $2k you can’t get an ionizer made of stainless. I guess the good thing about the ionizer is the water is flowing through it rather than sitting in it for days like the systems with a holding tank.
The distribution pipes inside my house and most new houses today are plastic. Not much I can do about that except move. I live in Colorado too, so I need a radon mitigation system also.
Somewhere there is a post about composite fillings containing BPA. I already got rid of the lead ones as I had high lead levels and replaced them with the composite.
What if you live in an Asian country where you must drink bottled water because normal water is undrinkable even to locals, food storage is always plastic because glass is unavailable or too expensive, cooking oil comes in plastic bottles and never glass, and everything comes wrapped in plastic ‘for safety reasons’?
One challenge my family is having is finding a way for storing emergency water long-term. We were able to acquire some food-grade 55 gallon drums used from Mountain Dew syrup or similar, but I think they probably have BPA in them. We do have town water at our home but we just want to have 150 gal +/- for any disruption/short-term contamination in the distribution from the municipal system.
Again Chris, another great topic.
I am having a hard time thinking of a good water solution. Yes, I can switch from my nalgene to a kleen kanteen, but the multi-gallon jugs of spring water I buy (to avoid the fluoride and other bad things that can’t be filtered out of tap water- which may come through plastic PVC pipes anyway) are made of plastic. Any suggestions?
So, this also ties in with the bromide toxicity via computer keyboards and mice. We should all start wearing gloves! 🙂
I found some nice glass storage containers with glass lids on the Container Store website. Look for “Vintage glass food storage”. Prices seem reasonable, too.
Seems to me that Ikea used to carry some glass canisters with glass lids, but I don’t think I saw them there recently.
Informative post! I have been plastic storage free for two years now. I know plastic is convenient for storage but with that convenience comes health repercussions.
There is a comment, in a later issue of the same journal, on the study that points out some real limitations:
In Vitro Detection of Estrogen Activity in Plastic Products Using a Sensitive Bioassay: Failure to Acknowledge Limitations
http://ehp03.niehs.nih.gov/article/info:doi/10.1289/ehp.1103894
I personally am comfortable using polyethylene and polypropylene after it has been through the dishwasher once.
You might check our response to the ACC note. (ACC is the plastics industry lobbying group)
http://ehp03.niehs.nih.gov/article/fetchArticle.action;jsessionid=5E871CE89670A65D82C7727EFB925525?articleURI=info%3Adoi%2F10.1289%2Fehp.1103894R
Good question, re: Brita.
I use Brita to filter my tap water at home, as the house was constructed in the 1920s and I am concerned about lead and copper in the pipes. Not sure what options are really available here.