Study Suggests BPA-Free Plastics Are Just As Harmful To Health (gizmodo.com)

An anonymous reader quotes a report from Gizmodo: Plastic products that boast of being "BPA-free" aren't necessarily any safer for us, suggests a new mouse study published Thursday in Current Biology. The chemicals used to replace BPA in these plastics can still leak out and affect the sperm and eggs of both male and female mice, it found. And these same effects could be happening in people. Bisphenol A, or BPA, is a chemical commonly used to create polycarbonate plastics and epoxy resins. These clear white plastics are themselves used in food and drink packaging, as well as consumer products and medical devices, while resins are used to coat metal products like canned foods. When these products degrade or are otherwise damaged (from being repeatedly heated in a microwave, for example), they can leach out BPA, exposing us to it. As a result, it's estimated that 93 percent of Americans have some level of BPA in their system.

While working on another project, the authors began seeing some but not all of their control mice, both male and female, develop reproductive problems. Though the mice had kept in cages made of polysulfone, not polycarbonate, the researchers noticed a whitish residue in some of the cages, indicating they had been damaged and were leaching chemicals. When Patricia Hunt, a researcher at the Center for Reproductive Biology at Washington State University, and her team analyzed the chemical signature of the damaged cages, they found both BPA and BPS, a bisphenol that is widely replacing BPA. The cases were polysulfone plastic, which is partly made from BPA, but it's advertised to be more heat and chemical resistant than polycarbonate and thus less likely to break down. Polysulfone isn't thought to degrade into BPS, but Hunt's team found that if certain chemical bonds in the plastic were broken in the right way, BPS could form. Following in the vein of their original experiments with BPA, Hunt's team exposed more mice to low doses of BPS, and compared their reproductive health to mice exposed to BPA and mice raised in fresh new cages, presumably free of any BPA/BPS contamination. The BPS mice had more defects in their egg and sperm cells than did the control mice, but the level of damage was similar to that seen in mice they exposed to the same dose of BPA alone. "Though manufacturers have shied away from making explicit claims about BPA replacements being safer, Hunt noted, customers have certainly assumed that they are safer," the report notes.

Comments

Newsflash: plastic is toxic

[DogDude]

Plastic is toxic. Always has been. Don't use it to wrap anything you eat or drink. It's not good for you.

Re:Newsflash: plastic is toxic

[Gravis Zero]

Plastic is toxic. Always has been.

The problem with that statement is that what's considered a plastic is chemical diverse. We do know some plastics do not have the kind of negative heath effects that BPA has because they are far more chemically stable. If you read the actual study, you'll see this is only in relation to "structurally similar bisphenols", not plastics in general.

The real problem we have here is that companies have been allowed to use any old molecular structure in their products they wish without proving anything about the health impacts it may or may not impart.

Re:Newsflash: plastic is toxic

[Solandri]

The real problem we have here is that companies have been allowed to use any old molecular structure in their products they wish without proving anything about the health impacts it may or may not impart.

Unfortunately, that's the only logical way you can do it. You cannot prove a negative - that's a fundamental tenet of the scientific method. If you push a hundred reindeer off a cliff and they fall to their deaths, you have not proven that reindeer cannot fly. All you've done is demonstrated that those hundred reindeer either could not or chose not to fly. OTOH, if you produce a single example of a flying reindeer, then you have unequivocally proven that reindeer can fly.

So you cannot prove that a newly developed chemical is not harmful. You can only prove if it is harmful. Consequently, the scientific way to handle newly developed chemicals is to assume they are safe until proven otherwise. You can run them through a preliminary gauntlet of tests designed to detect immediate or short-term toxicity. But long-term low-level toxicity as as appears to be the case with BPA requires years if not decades of data just to tease out a statistical probability that it might be harmful. If you required that all new chemicals be tested to root out that sort of low-level toxicity, nothing new would ever be developed because it'd be too expensive and take too long to approve for public release.

People want 100% safety, but practically that's an impossible goal to achieve. The best you can do is test for immediate toxicity, and recall chemicals which exhibit toxicity in the long-term after they've been in public circulation for a while.

Re:Newsflash: plastic is toxic

[Anonymous Coward]

Very true that you cannot prove that a chemical is not harmful.
But manufacturers of food containers can and should, however, be forced to prove that the food containers/liners do not leach into food under various conditions (with certain time, heat, acidity, other parameters).