You've heard of bisphenol A (BPA), right? Well, you should have. Especially if you're one of those people who carries their water bottle everywhere – from gym to your office desk – or if you use a plastic bottle to feed your baby.
BPA is a chemical that has been widely used in the production of certain plastics since the 1960s, including hard polycarbonate plastics commonly used for storing food and beverages and the plastic lining that covers the inside of many food cans.
BPA is known to leach out of these plastics and into the food and liquids they contain. This process is so prevalent that in the USA, traces of the substance are estimated to be present in the bodies of over 90% of the population.
According to the US Food and Drug Administration (FDA), however, there are no medical concerns associated with the very low levels at which BPA is typically observed in humans, and concentrations of five milligrams or less per kilogram of body weight are considered safe.
A recent paper published by FDA scientists at the US National Centre for Toxicological Research, for instance, suggests that rats exposed to low doses of BPA for 90 days while they were foetuses and after birth suffered no adverse health effects.
But not everyone agrees. Other scientists have criticised the FDA paper as severely flawed
and numerous independent studies contend that even at low doses, BPA can:
• affect the brain development and behaviour
of infants and small kids;
• cause impaired learning and memory;
• potentially increase the risk of cancer and heart problems;
• contribute to stress; and
• contribute to changes in metabolism and obesity;
Perhaps most distressingly, BPA is known to mimic the human hormone estrogen, potentially disrupting normal hormone function in foetuses and babies, and altering normal male and female sexual development and mammary glands.
So what do you do if you want to avoid BPA?
Public awareness of the growing health concerns has led to the introduction of BPA-free alternatives. Many manufacturers of baby bottles and sippy cups, for example, have eliminated BPA from their products.
As a result, you and I, as informed consumers, now have the option of circumventing the BPA controversy by only using BPA-free plastic containers and bottles.
Unfortunately that's not the end of the story.
New research indicates that some of the BPA-free plastics that are replacing the BPA-bearing ones also contain chemicals that mimic hormones and have the potential for disrupting the human endocrine system.
In agreement with a 2011 study, nine out of the 35 commercially available BPA-free children's sippy cups the US Center for Environmental Health sent for testing came back with "significant amounts of estrogenic activity". Seven were even found to have even higher levels of such activity than cups made with BPA.
These findings are being contested by plastic manufacturers who would prefer their customers not to lose any sleep over this sort of thing. Read this Mother Jones article for details on how the industry is attempting to suppress research investigating the health risks associated with BBA and BPA-free plastic products.
In writing about this issue, I'm not trying to panic you into an anti-plastic frenzy. I'm merely trying to share the fact that there is an ongoing debate about the topic which you should be interested in.
You may say that you've been eating and drinking out of plastic containers and bottles for your whole life without any negative side effects, and that you're quite happy to continue to do so in the future.
If you are concerned about the potential long-term impacts on you and your family, however, you may want to look for alternatives made out of glass, pottery or stainless steel wherever possible.
- Andreas is a freelance writer with a PhD in geochemistry. Follow him on Twitter: @Andreas_Spath
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