Published in the Sun June 30, 2012
Wouldn’t it be great if
experts could agree on which toxic chemicals don’t belong in our food supply? Instead, one group of environmental scientists
will warn that a certain chemical is turning all the little boy fishes into
little girl fishes, and then another group of scientists, usually the ones paid
by the makers of the maligned chemical, claim that it is safe enough to put
into baby bottles. The federal
government will eventually wade into the controversy, form a huge committee,
and proclaim that more studies are needed.
I am referring specifically
to bisphenol-A (BPA), widely used these days in hard plastics and epoxy
resins. Ninety-three percent of
Americans have measurable BPA in their urine, according to a study by the
Centers for Disease Control. Although
our bodies can get rid of BPA if the exposure stops, we are constantly re-exposed. Our main exposure comes from the epoxy resin
used to line the majority of food and beverage cans. Tiny
quantities of BPA leach into our vegetable soup or canned green beans or whatever
we threw on the stove for a 5-minute supper, so the more canned food you eat,
the more BPA you get.
We are also exposed to BPA by
drinking from polycarbonate bottles, the hard plastic ones that usually have a
number 7 on the bottom. A study of
Harvard students found that students who drank most of their beverages from
polycarbonate bottles for one week increased the level of BPA in their urine by
69%. In the past, baby bottles were made
with BPA, which is especially hazardous because parents tend to warm bottles in
the microwave. Heat dramatically increases
the amount of BPA that migrates into the milk or formula.
Nobody disputes that we are
exposed to BPA. The question is, “Does
it matter?” The dose makes the poison,
and the quantities in our bodies are very small, far lower than the level the
EPA says is safe for a chronic exposure.
However, there are researchers who believe the EPA is looking at the
wrong endpoints. BPA is an endocrine
disruptor; meaning that tiny quantities could have important hormonal effects
on sensitive cells, especially in a fetus or newborn baby.
BPA was first used as a
pharmaceutical agent in the 1930s to promote growth in cattle and poultry, and
later as a synthetic hormone in pregnant women.
It was eventually abandoned as a drug and taken over by the plastics
industry as a hardener for clear plastic.
In 1989 Dr. Ana Soto at Tufts
University School of Medicine found that her experiments exposing cells to
hormones went haywire when her test tube company started providing her with new
impact-resistant test tubes. Sure
enough, the new tubes contained a plastic hardener similar to BPA that was
causing her experimental cells to act as if they were being exposed to estrogen,
a female sex hormone. This discovery led
Dr. Soto to begin animal experiments with several plastic additives, including BPA. She discovered that at doses comparable to
what people receive in their daily lives, BPA could cause reproductive effects,
obesity, behavioral changes, and breast cancer in animals.
Over the following 20 years many
trees were cut down to publish the scientific papers linking tiny doses of BPA
to hormone-related disorders such as abnormal sperm development, heart disease,
prostate cancer, diabetes, and even obesity.
Not too surprisingly the plastic industry vigorously maintains that BPA
is safe at the levels to which we are exposed.
Despite the controversy, the
European Union, Canada, France, Denmark, Malaysia, Turkey, United Arab
Emirates, and China have all banned BPA from being used in baby bottles,
reasoning that while the experts continue to argue, it is better to be safe
than sorry.
The US Food and Drug
Administration, on their website devoted to BPA, states unequivocally that they
are “pursuing additional studies.” They
concede that since infants may be a sensitive population for BPA, they are
“supporting the industry’s actions to stop producing BPA-containing bottles and
infant feeding cups for the US market” and “facilitating the development of alternatives
to BPA for the linings of infant formula cans.”
In other words, if consumers want plastics without BPA, we should stop
buying BPA plastics. That would be a
fine strategy if the majority of consumers were well-informed about BPA, but
endocrine disruption is not high on the worry list for most people. Dr. David Ramsey, a Georgetown pediatrician,
says that he has never, ever had a parent bring up the topic of BPA in baby
bottles.
If you go shopping, you may
find some products or canned goods that say “BPA-Free”, but you won’t find any
that say “This product contains BPA” because what company would put that on
your canned food or plastic cup if they don’t have to? In 2009, Walmart voluntarily stopped selling
baby bottles made with BPA. Jen Sherwood,
an assistant manager at the Georgetown Walmart, also showed me the Cool Gear
BPA-Free plastic water bottles for adults which come in a wild assortment of
styles and colors. She has three of them
herself. Isn’t it interesting that
Walmart would be more concerned with consumer protection than the FDA?
I asked Dr. Joshua Long,
Environmental Studies professor at Southwestern, for his opinion on the
controversy surrounding BPA. He thinks
there is enough evidence from animal testing to support the toxicity of
BPA. He personally avoids BPA and avoids
giving it to his family.
If you want to take a few
prudent steps to cut down your BPA exposure, here are some suggestions.
1. Limit canned foods unless the cans are
BPA-free. Use frozen or fresh.
2. Use glass and ceramic dishes for storing (and
microwaving) food.
3. Don’t put plastics in the microwave. Even if containers are “safe” for the
microwave, hot liquids dramatically increase leaching of BPA (and other
chemicals) into your food.
4. Throw away your polycarbonate water bottles
(marked #7) and get some reusable metal bottles that don’t have a BPA
lining. Or just drink out of a glass.