Welcome to BPA awareness week on Scientifically Delicious. After posting my Turkey verde chili recipe back in December, a good friend from home asked how worried she should be regarding BPA and canned goods. I was slightly embarrassed because I hadn’t really given BPA a lot of thought up until that point. I know that I had heard a lot about it in the news, but I figured eh…it can’t really be that bad, plus I’ve been dealing with it for 30 years now, what can I really do about it? Then, that nagging voice in the back of my head convinced me to do some quick research and I was literally blown away by the amount of information that is out there regarding BPA and health.
This week, I will present to you some of the research I’ve gathered on what BPA is, how it affects you, how you can limit your exposure and other scientific goodies.
What is BPA, how was it developed and what is it used for today?
Bisophenol A (BPA) is a common chemical building block of polycarbonate plastic and epoxy resins. BPA can be found in plastic food containers/utensils, baby bottles, bottled water, dental sealants, microwavable containers, canned good lids and in the dust and air we breathe. It was estimated that 1.1 million tons of BPA was produced in 2007 in the U.S (with closer to over 2 million pounds documented more recently). At the chemical structural level, BPA is relatively unstable and lipophilic (fat-liking); indicating that it is likely to leach into food, especially when the container is heated (1).
BPA levels in humans?
A recent study done by the CDC indicates that 93% of the 400 urine samples taken from a national sample of adults were positive for BPA. Alarmingly, significant levels of BPA have also been found in pregnant women, breast milk, amniotic fluid, fetal and placental tissue as well as umbilical cord blood (1).
Does BPA accumulate in the body? One recent study, which enlisted 5 families to participate in a BPA-free diet (no canned foods or meals prepared outside, etc.), resulted on average with a 66% reduction in BPA levels after only 3 days. It’s important to note however, that levels did not decrease as rapidly as expected (BPA has a relatively short half-life and it typically cleared through the urine in a few hours-few days after exposure), indicating that BPA contaminates can be found in other sources (2).
What are some of the long term negative health affects associated with BPA?
Over 200 scientific studies have linked BPA with negative health affects. This list includes (but it not limited to): increased risk of breast and prostate cancer, male genital developmental abnormalities and infertility, early puberty in girls (average age jumped from 16 to 10 in recent studies), type 2 diabetes, obesity and neurobehavioral disorders. The levels found in humans is similar to that which has been used in animal models in scientific studies (3, 4). For a list of several scientific abstracts concerning BPA and disease, see this article from the Breast Cancer Fund.
Unexpected sources of BPA…
I think most of us by now recognize that BPA can be found in many types of plastics, with products like tupperware and bottled water getting the most awareness…but check out this list of unexpected sources of BPA exposure. (5)
- Drinking water
- Register receipts
- Dental sealants
- Children’s toys
- Beer, wine and soda containers
- Pizza boxes
- Toilet paper
- CDs and DVDs
- Car parts