A group called Environmental Defense has started to make noise and draw attention to findings that many canned products, including those from companies like Campbell’s or General Mills, frequently contain the chemical bisphenol A (BPA) in their linings.
Environmental Defense believes that this is a problem since it shows that some companies who pledged to reduce or stop the use of BPA are not doing so fast enough and that BPA can linings pose a health risk. Unfortunately, while the report’s findings of BPA can linings is likely accurate, the alleged risk to consumers is not.
BPA Can Linings: Quick Facts
- Bisphenol A is used in the lining of various canned goods to prevent food from coming into direct contact with the metal.
- BPA is a known endocrine disruptor and can cause behavioral problems or other health difficulties such as asthma and possibly breast cancer.
- In the Environmental Defense report, BPA was found to be in the linings and/or cans of 129 out of 192 (67%) of the tested canned foods.
- BPA is currently banned in Canada in the manufacturing of sippy cups and baby bottles.
- BPA is not used in US-based manufacturing of baby bottles, infant formula packaging, or sippy cups
On its face, this does seem like a serious problem. Canned goods are fairly ubiquitous in the market and there is no way to tell by examining a can that it is BPA-free or not, save for the small number that label themselves as such. The problem is that while Environmental Defense is correct in that these can linings probably contain BPA, and that BPA can be dangerous, they fail to understand that the two do not automatically add up to a consumer risk.
BPA’s Evidence for Safety
Environmental Defense cites several animal studies in support of its belief that the BPA in cans is a health risk. Generally speaking, these studies do show an effect on lab mice mostly related to exposure in the womb or shortly after birth with an emphasis on possible interactions with abnormal mammary development. Troubling? Yes. But animal studies are only one part of the picture.
Humans do not respond the same way to chemicals that animals do and while mouse studies are important, it is a bad idea to base safety claims on them when more relevant information is available. The FDA, fortunately, has given this situation more thought. In response to past concerns about BPA, the FDA has done numerous, rigorous studies and come up with a much clearer idea of how the BPA in can linings affects (or doesn’t affect) humans.
Various FDA Findings About BPA
- Humans at all ages metabolize BPA into an inactive form and excrete it much faster and with higher efficiency than rodents.
- Oral consumption of BPA is metabolized to an inactive form much faster than when it is injected, which it was in some of the mouse studies Environmental Defense cited.
- Due to human physiology and metabolism, only 1% of the BPA consumed actually ends up in the body in an active form.
- The FDA could not replicate some of the findings of prior mouse studies (changes to prostate or mammary glands, etc.) when it gave mice doses of BPA that were equivalent to the human low-dose range.
- In one case, the FDA found that feeding a pregnant rodent with 100-1000 times more BPA than people ingest through food could result in BPA being transmitted to the fetus. However, the detected levels in the fetus were so low they could not be measured and after eight hours they were undetectable completely.
When dealing with health effects or risks it is very important to remember that the dose makes the poison and that animal studies, while useful, do not always translate to human impact. Science is a gradual process that builds up more rigorous and human-relevant studies until a more accurate picture can be established. Although Environmental Defense is able to cherry pick its findings, the FDA’s more pertinent and human-relevant research speaks for itself.
Incidentally, although Health Canada has banned BPA in certain infant products, the agency itself admits that this is only done out of an abundance of caution and that BPA from food packaging is still not expected to pose a health risk to the public, including newborns or infants.
BPA: Bottom Line
- There is probably BPA in the lining of your canned foods.
- The amount of BPA in cans is nowhere near enough to cause harm to people whether infant, newborn, or grown.
- Companies pledging to reduce or remove certain chemicals is not evidence of harm, it is evidence of PR.
- There is a fine line between raising awareness of something and fear mongering.
Sources for Today’s Article:
“Bisphenol A,” Health Canada web site, last modified January 15, 2014; http://www.hc-sc.gc.ca/fn-an/securit/packag-emball/bpa/index-eng.php, last accessed March 31, 2016.
Breast Cancer Fund & Co., “Buyers Beware: Toxic BPA & regrettable Substitutes in the Linings of Canned Food,” 2016; http://environmentaldefence.ca/buyersbeware, last accessed March 31, 2016.
“Bisphenol A (BPA): Use in Food Contact Application,” Food and Drug Administration web site, last updated February 5, 2016; http://www.fda.gov/NewsEvents/PublicHealthFocus/ucm064437.htm, last accessed March 31, 2016.
