BPA out, BPS in: The Song Remains the Same

by Bill Chameides | January 31st, 2013
posted by Erica Rowell (Editor)

That “BPA free” label on the bottle you just bought does not necessarily mean toxin-free.

Lisa Jackson, the outgoing administrator for the Environmental Protection Agency, put it rather bluntly: when it comes to protecting the public from toxic chemicals in consumer products, “we are failing to get this job done.”

She went on: “The Toxic Control Substance Control Act (TSCA) has “fallen behind the industry it’s supposed to regulate — it’s been proven an inadequate tool for providing the protection against chemical risks that the public rightfully expects.”

What’s the problem? Put simply, the law seems unable to make sure that the chemicals added to our consumer products are safe. And when there does appear to be a problem, the process laid down by the law is so byzantine it makes a rapid governmental response problematic.

If you ever needed an example of the problem, the sad, unfolding story of BPA and its cousin BPS should suffice.

Bisphenol A – the Plastic Compound We’ve Learned to Hate

Bisphenol A or, more affectionately, BPA, as I’ve described in a number of posts on TheGreenGrok, is one of 39 chemicals that have a common chemical building block: a bisphenol group (C12H10(OH)2). Taken together, the bisphenols are a remarkable set of chemicals — and I am not using the work “remarkable” in a positive sense. According to a 2008 report (see page 11) [pdf] of the National Toxicology Program, many of them are listed as endocrine disrupters or potential endocrine disrupters of one sort or another.

BPA is made by adding two methyl groups (CH3) to the basic bisphenol building block. It was first synthesized in the lab in 1891, and has been known to act as a synthetic estrogen since the 1930s. Despite its known estrogenic properties, BPA began finding its way into plastics in the 1950s.

Today it is an invisible component lurking in myriad everyday goods. Even if you bought a BPA-free water bottle for the gym this morning, chances are you’ve come into contact with it from one or more products in your home or office or even your wallet. A key ingredient in polycarbonates, a popular form of plastic, there is still BPA in many plastic bottles,* as well as compact discs, dental sealants, the linings of about 85 percent of canned foods (though that is changing) and in many cash register receipts (which means that even paper money now has BPA on it and so we’re spreading it around even more). (See more here, here and here.)

Within the last decade or so (though the earliest concerns can be traced to the 1980s) evidence began mounting that BPA could leach out of plastics especially if heated (or exposed to UV light [pdf]). And if BPA is leaching out of plastic bottles and canned foods, odds are that we’re ingesting it. And that certainly appears to be the case.

Studies have shown that BPA is found in the large preponderance of Americans (90+ percent). And in keeping with its toxicity, BPA has been linked to a variety of diseases — from problems with the brain and the prostate to problems in the reproductive system and childhood development, as well as heart disease and diabetes.

The Pivot Away From BPA

The negative publicity about BPA — its leaching out of plastic bottles and its health risks — raised a firestorm among consumers. Advocacy organizations began to call for a ban on the use of BPA (See here, here and here) and states followed suit. Between about 2009 and 2011, Connecticut, Minnesota, Wisconsin, Washington, Chicago and Suffolk County, N.Y. banned [pdf] “the sale of polycarbonate baby bottles, food containers and cups that contain BPA. The Connecticut ban also applies to infant formula cans and all reusable food and beverage containers.”

So spectacular were consumer protests that the chemical industry responded on its own. Consumers were finally given the option of buying “BPA-free” water bottles and shortly after that the chemical industry voluntarily stopped the use of BPA in baby bottles. The chemical industry then asked the Food and Drug Administration to make the ban official and in July of 2102 the FDA banned the use of compound in baby bottles and sippy cups.

A Toxic Response System That Works?

It’s rather impressive. A toxic compound is found in the marketplace, consumers get upset, the industry responds, and we’re a little bit safer. Lisa Jackson’s statements about “failing” and “inadequate tools” notwithstanding, it seems that the system can kind of work. Right?

Not quite. In the first place, if we had a system for dealing with toxic substances in consumer products that really worked, maybe we would not have had any BPA in any plastic baby bottles  (or any other bottles and cans) to start with.

And there’s an even more disturbing chapter to this story.

Bisphenol S – A Better Compound?

Once plastic manufacturers knew BPA-free plastics would be needed for at the very least baby bottles and sippy cups, you’d think that clearly, given the history with BPA, they’d sub in a chemical totally (or close to totally) benign. Right? Nope.

As it turns out, one of the replacements for BPA is BPS  — another bisphenol compound, in which a sulfonyl group (a sulfur atom bonded to two oxygen atoms) is added to the basic bisphenol building block. Probably not a great choice.

While BPS doesn’t leach out of plastics as readily as BPA under high temperatures, it does leach out and is more persistent — meaning it sticks around more, upping the chances of accumulating in the environment and in us.

As far back as 2005, scientists knew that BPS displayed xenoestrogen (endocrine-disrupting) properties. Now, a paper by René Viñas and Cheryl Watson of the University of Texas Medical Branch Galveston published in the journal Environmental Health Perspectives found that BPS’s ability to disrupt normal hormone activity in animal cells occurs at very low levels.

It’s the same ole story — one step forward, two steps backward. The names of the compounds may change, but the song remains the same. And will, until we change the way we allow chemicals to enter the marketplace.

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End Notes

* BPS has been identified as a general substitute for BPA in thermal paper and in European manufactured baby bottles. It is probably not the only substitute, and if that’s not enough to get your goat, a 2011 study found that many plastics (even those that are BPA-free) have estrogenic activity.

filed under: faculty
and: endocrine disrupters, endocrine disruptor