Going Another Round in the Never-Ending BPA Debate
Going Another Round in the Never-Ending BPA Debate
Editor's Note: An earlier version of this story described C&EN as a publication of the American Chemistry Council, when it is actually a publication of the American Chemical Society.
If you walk through the baby-products aisle of a big-box retailer, you could be forgiven for thinking the controversy around bisphenol A (BPA) was settled. The chemical, which has been implicated in developmental problems, diabetes and other health issues, has been pulled from many baby items and water bottles, and has been banned in some uses by Minnesota, China and the European Union, among other places.
But a series of features in Chemical & Engineering News yesterday highlights the fact that not only is the debate about BPA's impacts very much alive, but that there are still a number of sources of exposure to BPA that haven't been addressed, and that no alternative has yet been widely adopted.
It all boils down to the fact that BPA continues to be one of the murkier chemical issues companies have to wade though.
C&EN (a publication of the American Chemical Society) has put together, as part of their series on BPA, an exhaustive look at the numerous studies, bans and more actions on BPA. In short:
On one side of this debate, consumer and environmental advocacy groups who emphasize potential health problems stemming from steady, low-level exposure to BPA support their position by invoking the precautionary principle, which holds that even in the absence of scientific consensus it’s prudent to act as though a potentially harmful substance is, in fact, harmful. They argue that there is already enough scientific evidence of BPA’s toxicity to warrant a ban and that the general population shouldn’t have to be human guinea pigs while waiting for more compelling evidence.
On the other side of the debate, manufacturers and chemical industry groups out to protect a multi-billion-dollar market from regulation are defending BPA as safe. They say the problem with applying the precautionary principle is that it could lead to a ban on a useful chemical that poses no actual danger.
BPA, an estrogen-mimicking chemical, has been used in hard plastic water bottles, baby bottles and other infant items, epoxy resin liners in canned food, receipt paper, CDs, some sports equipment and numerous other items. Numerous lab studies have linked BPA to a host of negative effects like reproductive and developmental problems, diabetes and more.
While companies were quick to remove BPA from water bottles and baby products, or at least also offer BPA-free choices, it's been more challenging for companies trying to get BPA out of canned food. In addition, concerns have been raised that some replacement chemicals are from the same family as BPA and can have the same effects.
In a look at some of the alternatives being explored, C&EN notes successes like Eastman Chemical Company's Tritan material, as well as issues with some replacements.
Among BPA-free alternatives being explored, glycol-modified polyethylene terephthalate, a type of copolyester, has clarity and processability comparable with polycarbonate...But the copolyester is still not quite as tough or heat-stable as polycarbonate and has a slightly higher cost
Another BPA-free replacement plastic is polyether sulfone...(it) is very stable and holds its properties over a wide temperature range, (Stuart I.) Yaniger, (vice president of research and product development at PlastiPure) says, but the polymer is significantly more expensive and still triggers a positive response in estrogenic activity assays.
And the list and trade-offs go on.
Making the issue even murkier is new information and discussions about the many ways BPA can get into people, calling into question how much BPA people are exposed to on a regular basis and which sources are the most important to deal with. From another C&EN article:
“When it comes to BPA in the environment, the biggest exposure, in my opinion, is from cash register receipts,” says John C. Warner of the Warner Babcock Institute for Green Chemistry (WBI), in Wilmington, Mass. “Once on the fingers, BPA can be transferred to the mouth, onto food, and likely absorbed through the skin.”
Yet others like the World Health Organization point to food as the main way BPA gets into people, a U.S. Environmental Protection Agency study found food was the main way BPA gets into preschoolers, and a new study out of the University of Missouri claims that previous lab studies on BPA have underestimated how much BPA people are exposed to on a regular basis.
For the study, researchers looked at BPA levels in mice given a steady diet that included BPA compared to mice given a single exposure of BPA, finding that BPA levels in first group were higher. Somewhat similar was a study on humans that found BPA levels dropped in people if they changed their diet to avoid sources of BPA, and those levels went right back up when they switched back to normal diets.
Between the ACS's series on BPA and other actions being take by governments and industry — 17 states could look at BPA bans this year; the metal can manufacturing trade alliance says BPA is safe, but is looking at alternatives — it's clear the debate is going to continue for some time, leaving shoppers and product manufacturers alike in a BPA limbo.
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