Bisphenol-A or BPA - a substance that is used in food packaging such as in the epoxy lining of food cans and in polycarbonate bottles has been a subject of intense controversy and concern over the last few months.  On Nov 11, I wrote a post listing the specific canned and other foods that were of concern vis-a-vis BPA ingestion, and earlier in June this year, I wrote about the results of a Harvard study that confirmed the leaching of BPA from polycarbonate plastic bottles.   This month, additional research on BPA has brought to surface new and pressing health concerns regarding the ingestion of this chemical.

A recent study by the French National Institute of Agronomic Research (INRA) found that BPA caused a negative reaction in the intestine of rats - even at doses that were 1/10th of the  daily amount considered safe for humans.  Results from this study suggested that BPA lowered the permeability of the intestines and the immune system’s response to digestive inflammation, and that newborn rats exposed to BPA in the uterus and during feeding had a higher risk of developing severe intestinal inflammation in adulthood.  Previous studies on BPA have indicated that high levels of this chemical in the bloodstream are significantly associated with heart disease, diabetes, and abnormally elevated levels of certain liver enzymes, and furthermore, that BPA exposure during development has carcinogenic effects and produces precursors of breast cancer.

In light of the cumulative evidence indicating numerous concerns with BPA consumption, The National Institute of Environmental Health Sciences (NIEHS) and the National Toxicology Program have warned people – particularly pregnant women and children – not to consume BPA.  The NIEHS has also launched a $30 million research initiative to investigate the effects of BPA, and the United Nations will be holding a summit on BPA safety in 2010.

BISPHENOL-A AND YOUR HEALTH – WHAT YOU CAN DO NOW

Given the mounting evidence indicating that ingestion of BPA may lead to significant health problems, it appears prudent to minimize exposure to BPA via food packaging that utilizes this chemical.  While the US Food and Drug Administration has not yet issued the final word on BPA safety (It has postponed release of its final report), research does indicate that there is significant evidence and good reason to be concerned about BPA consumption.  For this reason, you should carefully review and act on the guidelines presented in previous posts (links above) to minimize BPA exposure.  Here are some key reminders:

1.  Review products that have been found to have high levels of BPA  and minimize or avoid their consumption altogether (These particularly include canned green beans, canned soups, and certain canned juice drinks).

2.  Choose fresh over canned or packaged foods whenever possible.

3.  Do not reheat food or drink in the microwave in plastic containers – Use only glass.

4.  Do not consume food or beverage from containers with the numbers 3 or 7  listed inside the recycle symbol on the container.

IN THE FINAL ANALYSIS…

….I feel both obliged and compelled (in my position as a research scientist, and by virtue of my experience is studying chronic diseases) to share with all that nearly everyday I meet people who “wonder” where their particular chronic disease “came from.”  While it is true that even with all the tools and knowledge at our disposal, we are sometimes unable to discern the ultimate cause(s) of certain diseases, I find that most of us do not begin to take full advantage of the facts we do know that can help us minimize the prospects of disease.  

In Medicine, we learn that, “A disturbed biochemistry is always the antecedent to observed pathology.”  In simple language, that statement simply means that before a disease fully manifests itself, there is almost always (that is, in most cases) a window of time in which we may be able to prevent the disease and/or alter its course.   Given that fact, I wonder how many of us truly take seriously the power that is vested in our own hands both to prevent and/or alter the course of a great many diseases.

Increasingly, in the US and the West, the list of environmental and other exposures that may have  a detrimental, and perhaps even a fatal effect on our health appears to be increasing.  BPA is yet another exposure against which evidence indicates serious caution may be warranted.  Notwithstanding that fact, I have been told that many are going to find it “impossible” to choose fresh green beans over canned, or to undergo the inconvenience of not warming foods in plastic ware.  This is just a friendly reminder to all that it can be exponentially more inconvenient to deal with disease when it occurs, especially in contrast to the “inconvenience” caused by taking the relatively simple steps that can be taken to avoid it.   The window of time to minimize the risk of disease in now; the power to do so is in our hands.  Let’s be sure to use it, and use it well.

BPA – BACK IN THE NEWS

BPA is back in the news this month as a result of recent testing of canned products.  Consumer Reports’ latest tests of canned foods, including soups, juice, tuna, and green beans, have found that almost all of the 19 name-brand foods tested contain some BPA.  The highest levels of BPA were found in some samples of canned green beans and canned soups.  Here are some of the key results of the tests:

• Canned Del Monte Fresh Cut Green Beans had the highest amount of BPA for a single sample in Consumer Reports tests, with levels ranging from 35.9 parts per billon (ppb) to 191 ppb. 
• Progresso Vegetable Soup BPA levels ranged from 67 to 134 ppb.  Campbell’s Condensed Chicken Noodle Soup had BPA levels ranging from 54.5 to 102 ppb.
• Average amounts in tested products varied widely. In most items tested, such as canned corn, chili, tomato sauce, and corned beef, BPA levels ranged from trace amounts to about 32 ppb.
• Nestlé Juicy Juice in a can averaged 9.7 ppb of BPA, but there were no measurable levels in the samples of the same product packaged in juice boxes.
• Similac liquid concentrate (infant formula) in a can averaged 9 ppb of BPA, but there were no measurable levels in the powdered version.
• The canned organic foods tested did not always have lower BPA levels than non-organic brands of similar foods analyzed.  Further, the tests also found the chemical in some products in cans that were labeled “BPA-free.”

There is still significant debate surrounding safe levels of BPA that may be ingested, or whether this chemical should be in contact with food at all.  New guidelines vis-a-vis safety levels of BPA in light of new data are presently being worked out by the FDA.

MY COMMENTS

While the jury is still out regarding the final safety levels of BPA ingestion, I believe that there is significant epidemiologic data to merit caution with respect to BPA consumption.  Previous studies have demonstrated that BPA exposure is significantly associated not only with heart disease and diabetes, but also has carcinogenic effects as it may produce precursors of breast cancer.   Consequently, it is prudent to err on the side of caution with respect to levels of BPA ingestion and exposure. 

HERE ARE SOME CRITICAL TIPS TO MINIMIZE YOUR EXPOSURE TO BPA:

1.  Whenever possible, choose fresh over canned foods, beverages, juices, etc.  Minimize the use of canned foods.

2.  Do not heat food/beverages in plastics or expose plastics to hot liquids.  BPA leaches out 55 times faster upon heating that it does under normal conditions.

3.  Use only glass containers in the microwave for heating foods and liquids.  Avoid microwaving food in plastic containers.

4.  Avoid using all food and beverages from containers that have the numbers 3 or 7 listed inside the triangular recycle symbol on the package.

5.  Read and stay informed!  Most people overlook this last critical point.  BPA research is an emerging field of study, and it is crucial to stay well-informed on a topic such as this one.  Start by reading my previous post on this topic that summarizes results from key epidemiologic studies, and please forward this current post to all who may benefit from it.