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Bisphenol A – Getting More Powerful Everyday

So is it Mondays with Bisphenol?? You know what, the scary thing about this chemical is that its acute (short term, immediate) toxicity at high doses, which is the only safety testing that is ever done, does not correlate with all the subtle effects that are seen at low doses (chronic). Here’s another study where ambient level exposure to bisphenol A interferes with prostate cancer treatment by making the tumor cells androgen independent, so the standard testosterone deprivation therapy will not work any more.

Environmental Health News: New Science

A common plastic molecule to which virtually all Americans are exposed may interfere with the standard medical treatment for prostate cancer, according to new experiments with human prostate tumors implanted into mice. The doses of the plastic molecule, bisphenol A, were chosen specifically to be within the range of common human exposures. Tumor size and PSA levels were significantly greater in exposed animals just one month after treatment.

One of the principal known sources of exposure to bisphenol A in the U.S. is through its use to make a resin that lines the majority of food cans sold in markets. These new results by Wetherill et al. suggest men concerned about prostate cancer may want to reduce their consumption of canned goods and their use of polycarbonate water bottles, another common source of exposure

This is one powerful (if not actually more dangerous) chemical. it is so ubiquitous that finding a substitute is not going to be easy.

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    Source wikipedia.
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3 Comments

  1. Although there seems to be such a great deal of debate over this issue of BPA safety, this issue is not so fuzzy. Every independent body that has reviewed all of the research on BPA has come to the same conclusion, BPA is safe as a food contact material. Why would this be the case when all you hear is so many bad effect associated with BPA? These independent agencies give studies a score on relevancy to human health. So when you see in the press that BPA is associated with certain effects, that makes for great press, but what you may also miss, because it is not printed, is that most of these effects were seen in animals that are not like humans, with dosing methods not like human oral exposure (often subcutaneous injections, not sure how many humans inject BPA into their bloodstream), and at levels far above what humans are exposed. Now to top it off you need to also know that this issue has become the new item for many environmental groups. They want to push their agenda on this issue. It is also important to remember that not every environmental group is the same. A good example of this is the Environmental Working Group, they recently published a report on BPA in canned foods (which by the way shows that every sample was at least 10x below the lowest regulated amount). But what is the EWG’s true motivation? Well, as their main funding on this issue comes from trial lawyers I think we now see what their real agenda is. As was highlighted several months ago by the woman who dies from drinking too much water for a radio show contest, every chemical is dangerous when taken in high enough doses. Does this mean we should ban the use of water?
    I know it may be hard to believe, but it may just be that the FDA, European Food Safety Authority, and the Japanese Ministry of Health are right on this one. BPA is safe as a food contact material. But that is just not convenient for the trial lawyers!!

  2. So, I am to believe that a cabal of environmental groups and trial lawyers have hatched a conspiracy to destroy this poor chemical and the manufacturers that make it?? Please!!

    I don’t think BPA is near a point where it warrants a complete ban. However, the research into BPA is very interesting to me because it highlights the flaws in our model of setting exposure levels. We test in animals at high doses and look for acute effects. We apply a safety factor and call that the acceptable dose. With BPA, scientists are finding that at very low, ambient exposure levels, there are very subtle hormonal effects that result in significant endocrine disruption over generations. This research points to the fact that the dose-response relationships for BPA are likely non-linear. That is, a response at a low level cannot be extrapolated from a dose at a high level. What’s worse, the mechanism of response seems to be different, and more powerful at low levels rather than high levels.

    Your comment about water is an obvious strawman and not worth responding to.

  3. Am I to understand that you think it is impossible for the trial lawyers to have taken on this issue to milk it for everything it is worth. Look what they did with asbestos. They ran so many companies bankrupt by signing up anyone who ever stepped foot into a plant that may have had some asbestos in it that there is little money left to pay people who are really injured, oh but they are all rich.
    The research on BPA is very interesting, but why does every “independent” government body who reviews the full research, not that which is spun by groups like EWG, do they come to the same conclusion. A good example is recently hatched idea that BPA causes obesity, well if that were true would not every other study on BPA where the 1st thing you do is weigh the animal have found that. But obesity is another hot topic so why not attach that claim to BPA too, even if there is no data to support it. Usually that is a sign that science is lost and other agendas have taken over when they start throwing the kitchen sink at it (like obesity).

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