Tuesday, August 31, 2010

BPA: The Facts

With the recent news about the high levels of exposure to BPA in credit card receipts, I thought it might be a good time to provide a quick guide to the history, facts, and risks surrounding BPA.

The History
Bisphenol A (aka BPA) was developed and released in 1891 by Russian chemist Aleksandr P. Dianin. The "A" stands for acetone, which is commonly known as a solvent but is also naturally produced in the body.

BPA is most commonly used in the production of polycarbonate plastics and epoxy resins. It has been used in plastic products for over 50 years. Polycarbonate plastic is used in the production of many common items, including: CD's and DVD's, lenses, bottles, sporting equipment, appliances, and medical and dental devices. The epoxy is most widely used for the lining of nearly every food and beverage can.

Something to keep in mind while reading this: in 2007 it was announced that the average levels of BPA in people are above those that cause harm in lab animals. BPA, because it is so common in our daily lives, affects every person.

The Problems
BPA has been known to be estrogen mimicking since the 1930's. Several studies have now been released, dating back to the late 1980's. These tests show strong link between BPA exposure (including fetus exposure) and brain, behavior, prostate, mammary gland, development, and obesity problems. It has been shown to bind the thyroid hormone receptor. BPA is a known endocrine disruptor, but it had been declared safe. The Endocrine Society released a statement resulting in a second look at these "safe" test results. Tests are currently underway.

Studies done in 2008, 2009 and early this year have shown that even low exposure to BPA can contribute to abnormalities in breast development. Data that has been gathered over the last several years and animal tests that have been performed strengthen the hypothesis that BPA exposure could be an underlying cause in the significant increase in breast cancer incidents over the last 50 years. BPA may also reduce sensitivity to chemotherapy treatments.

And men, don't think you're excluded! BPA (within the range of concentrations currently measured in humans) is linked with permanently increased prostate size. In addition to several other issues, it is also linked specifically with male sexual dysfunction.

Marine life is also severely affected by BPA that leaches into the water from plastic trash. Because their skin is so much thinner (fish in particular) than humans, the BPA is much more potent. Fish become sterile, have abnormalities, and/or come up with toxic readings in sample testing.

BPA in Credit Card Paper
So why is something that is used in plastics and epoxy in credit card paper? BPA is also used as a color developer in thermal paper (like that used for the majority of credit card receipts) and carbonless copy paper. A layer of BPA and invisible ink is placed between paper. When heat, primarily, is applied, color shows up. Neat trick, huh? It is so popular because ink doesn't have to be used in the machines to print receipts.

Here is the problem. When polycarbonate bottles first start to leach, there is only very small amounts of BPA (think nanograms) released. EVERY BPA receipt contains 60-100 mg of free BPA. Free BPA means that, unlike polycarbonate BPA, which is chemically bound to polymers, this BPA is pure and floating around, ready to be inhaled, absorbed, or rubbed onto something that we eventually ingest.

The Upside
There are only a handful of companies in the United States that produce BPA. One of the producers, Sunoco, is now refusing to sell the chemical to any company that manufactuers products intended for children under the age of 3 (when humans are supposedly most susceptible to BPA). The 6 largest baby bottle manufacturers are BPA free.

Legislature has been passed in several states banning BPA in bottles. Internationally many forward-thinking countries are beginning to ban any products that contain significant amounts of BPA.

General Mills (the owner of one of our favorite brands, Muir Glen) has found a suitable alternative to the BPA epoxy for canned tomatoes. Tomatoes are highly acidic and it has been difficult to find something tough enough, and safe enough, to keep tomatoes in cans. They are now using this blend for all canned tomatoes (and we're guessing they are probably using it for the rest of the line, too).

The best way to combat the BPA on the receipts is to wash or sanitize your hands frequently- ESPECIALLY before eating- and don't leave them sitting in a place where the BPA can rub off on other items you commonly use (e.g. a purse, cup holders in your car, et cetera).

No comments:

Post a Comment