BPA in can linings and plastics may impact our health
What’s strong, flexible, and ubiquitous, allegedly causes a laundry list of medical issues, and is still not banned in Pennsylvania, despite having been so in 12 other states as well as Europe? Well, bisphenol A (BPA). BPA has been linked to numerous issues that especially affect children both inside and out of the womb, being negatively associated with brain development, reproductive system development, and Down syndrome. It has also been linked through some studies to behavioral issues in young children. Possible BPA impacts in adults include difficulty in reproduction and conception, miscarriages, diabetes, obesity, cancer, and many other serious health issues.
So what, exactly, is BPA? BPA is an industrial chemical that has been used since the 1960s to make various plastics and resins, such as polycarbonate plastics and epoxy resins. These are used in food and beverage storage containers, the most contentious of which have been infant and children’s bottles and cups. The resins are also used to coat the inside of metal products, such as canned goods, bottle tops and water-supply lines. Some dental sealants may contain BPA, as well as toilet paper, register receipts, and paper money—and the list goes on. Initially, BPA was added to these plastics in order to make them “safer”—at least in the sense that they would not shatter. An example of such an application would be the well-known children’s “sippy cup.”
What should be a seemingly non-divisive, health-related issue has given rise to professional bickering and disagreements between the chemical industry, the federal government, and independent researchers. At the center of much of the controversy since the 1970s stands Dr. Frederick vom Saal, University of Missouri, Columbia, and senior author of a definitive study on low-dose BPA exposure, published in the journal Reproductive Toxicology, in July 2013. “What’s scary is that we found effects at levels that the government not only says is safe, but that they don’t bother to test,” wrote vom Saal. Standard high-dose testing has not yielded any results worthy of raising red flags among so-called conventional researchers.
Nevertheless, BPA’s role as an endocrine disrupter is not in dispute. As vom Saal states, “Low doses of endocrine disrupters act in ways that are totally unpredicted by the traditional approaches of toxicology.” That is to say, per vom Saal’s studies, very low doses of compounds such as BPA have been shown to give rise to the array of health issues previously listed. In toxicological jargon, this behavior manifests as “non-monotonic dose-response curves.”
The widespread application of BPA makes it difficult to avoid, so much so that very few people would not test positive for the compound in their urine. And while there have been many successes in eliminating bisphenol A from consumer products, especially in Europe, there exist substitute compounds in the bisphenol chemical class. There are, in fact, no fewer than 15 “bisphenols”: A, AB, AF, B, BP, C, E, F, G, M, S, P, PH, TMC, and Z0. These compounds may have deleterious effects similar to those of BPA, including male impotence, altered sex hormones in men, depression, asthma, breast cancer, type 2 diabetes, and heart disease in women. BPS is also more insidious than BPA, as it is less biodegradable, and therefore, may have a more lasting harmful effect on health.
Dodging the ubiquitous bisphenol compounds may be a challenge, but it can be done. The Mayo Clinic has suggested the following steps: Look for BPA-free products. While some are labeled as BPA-free, plastics marked with recycle codes 3 or 7 may contain BPA. Avoid the use of cans that do not have “Manufactured without BPA” printed on them, when at all possible. It is especially important to avoid cans with BPA that contain tomato products, as the acid in tomatoes rapidly breaks down the can lining, causing BPA to be released quickly and fully into the food. Muir Glen Organics, among others, sells tomato products in cans not lined with BPA, and these may be found at our local Wegmans Food Market. Another strategy is to avoid heating anything in a plastic container. Heating breaks down the plastic, allowing BPA to leach into foods. Instead, use glass, porcelain, or stainless steel containers for hot foods and liquids.