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Biotech Earth Science

'Zombie' Hormone Disruptors Rise From the Dead 67

ananyo writes "Hormone-disrupting chemicals may be far more prevalent in lakes and rivers than previously thought. Environmental scientists have discovered that although these compounds are often broken down by sunlight, they can regenerate at night, returning to life like zombies (abstract). Endocrine disruptors — pollutants that unbalance hormone systems — are known to harm fish, and there is growing evidence linking them to health problems in humans, including infertility and various cancers 'Risk assessments have been built on the basis that light exposure is enough to break down these products,' adds Laura Vandenberg, an endocrinologist at the University of Massachusetts in Amherst who was not involved in the study. 'This work undermines that idea completely.'"
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'Zombie' Hormone Disruptors Rise From the Dead

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  • Interesting... (Score:5, Interesting)

    by fuzzyfuzzyfungus ( 1223518 ) on Friday September 27, 2013 @09:27AM (#44970593) Journal
    I assume that there simply weren't as many endocrine disruptors in the wild, so it was less of an issue over evolutionary time; but for (modestly complex) chemicals to be photosensitive enough to degrade; but suitably structurally favored to have more than a remote probability of being created by the recombination of their breakdown products is rather interesting...

    Would it be in any way adaptive for hormones themselves(which disruptors are often very similar to, hence the ability to neatly disrupt the endocrine system) to have this level of durability, or is it much more likely that it's mere chance, biologically irrelevant until we started pumping the things out on an industrial scale?
    • The issue may be that while they are broken down, they aren't broken down to their constituent elements. Or even to naturally occurring compounds, it's more that the products of degradation are supposed to be [relatively] inert.
      • , it's more that the products of degradation are supposed to be [relatively] inert.

        I think this is the key. As FFF said, it's interesting that the apparent activation energy to flip between active and inactive is fairly small. The good news is that it should be 'easy' to treat runoff such that you really do destroy the bioactivity - you probably don't need large amounts of energy to do so. The bad news is that dumping metric shit tons of the stuff in a small, slow flowing creek isn't going to solve the problem and you will have to build a treatment plant.

        Farmers hate that.

        What some asp

        • by mspohr ( 589790 )

          I'm not sure that it would be "easy" to treat runoff. The article points out that the synthetic steroids are changed in daylight but then reform at night. It also points out that we can't assume that the "broken down" molecules are safe. Currently they only test for the specific original molecule but it could be that the broken down molecules are also bioactive.
          They recommend using a bioassay (which tests the water on living systems) rather than just a chemical assay for the original compound.
          Another proble

        • Close. Most stimulants are dopaminergic, which is a catecholamine and only has a single ring; (nor)epinephrine are also in that family. The indole backbone is in the tryptamines, including serotonin, and in psychotroptics like psilocybin. Also present in LSD, although given how monstrous that molecule is, it doesn't figure as prominently as a 'backbone'.

          That said – I'm not sure we really want to seed our water with a substance that converts a broad family of small organic molecules into psychotropic
  • by Anonymous Coward on Friday September 27, 2013 @09:29AM (#44970607)

    Chemicals are your friends. Untested chemicals are your untested friends.

    • by i kan reed ( 749298 ) on Friday September 27, 2013 @10:31AM (#44971377) Homepage Journal

      "Chemical industry" isn't a thing that exists, is it? Most of these are from agricultural run-off, aren't they? The article certainly seems to suggest that. What you're really hating is modern farming practices.

      • The modern farmer uses chemicals produced by chemical companies all over the place...
      • "Chemical industry" isn't a thing that exists, is it?

        Of course it is; the chemical industry makes all the chemicals that everybody else (including agriculture) uses. Major corporations include BASF, Dow and DuPont.

        • "Chemical industry" isn't a thing that exists, is it?

          Of course it is; the chemical industry makes all the chemicals that everybody else (including agriculture) uses. Major corporations include BASF, Dow and DuPont.

          Let us not forget Monsanto, still the world's largest producer of a number of nasty compounds including glyphosphate.

          • Glyphosate has been off patent for while. The Chinese produce most of it and there are trade cases based on dumping it on export markets now.

            • Glyphosate has been off patent for while.

              And yet, Monsanto and their worldwide subsidiaries are/is still collectively the single largest producer.

  • by TWX ( 665546 ) on Friday September 27, 2013 @09:30AM (#44970623)
    Anyone else getting tired of zombies? They're starting to appear in bad corporate cell-phone ads now.

    It was cute for awhile, but there seem to be people taking it seriously enough that they're changing their lifestyles based on the idea. It's silly.
    • by sjames ( 1099 )

      Yeah, but the zombie meme keeps getting back up and shambling around the internet looking for braaaaaaainnnnnns.

  • by the eric conspiracy ( 20178 ) on Friday September 27, 2013 @09:42AM (#44970763)

    There a lot of serious problems with doing risk assessment for endocrine disruptors.

    The first is that there is no known mechanism for most of the effects reported in the literature. Without this mechanism a real science based approach is impossible.

    The second issue (and a general problem for that matter) is that many of the studies reported turn out not to be reproducible.

    The following articles give some insight into this, relative to BPA which has been (possibly without justification a cause celebre):

    http://munews.missouri.edu/news-releases/2013/0102-previous-studies-on-toxic-effects-of-bpa-couldn%E2%80%99t-be-reproduced-says-mu-research-team/ [missouri.edu]

    http://www.ncbi.nlm.nih.gov/pubmed/21438738 [nih.gov]

    • "The first is that there is no known mechanism for most of the effects reported in the literature. Without this mechanism a real science based approach is impossible."

      That's a bit strong, isn't it? We've spent how long now have either absolutely no clue or fancy-dubiously-verifiable-math to explain this 'gravity' nonsense, without appreciable harm to many of the disciplines that include it as a major part of their theoretical structure...

      Sure, having to do your testing along the lines of statistical s
    • by nomadic ( 141991 )
      A science-based approach is certainly possible based on empirical studies; 300 years of successful science has shown us that; look, for example, at John Snow's discovery of the source of the 1854 cholera outbreak in London (http://en.wikipedia.org/wiki/1854_Broad_Street_cholera_outbreak). He didn't know the mechanism of contagion but he didn't have to in order to stop the outbreak.

      Anyway, there is plenty known about the mechanisms of endocrine disruptors, specifically that they can mimic endogenous hormo
      • by tgibbs ( 83782 )

        The problem is that the concentrations of these agents in the environment tend to be extraordinarily low compared to the hormone levels that are normally present in the body, so it is hard to understand how they compete appreciably with the natural hormones. That doesn't mean it's impossible for these substances to have biological effects, but some explanation is needed beyond "they can mimic hormones."

    • by mspohr ( 589790 )

      I think the mechanism is "endocrine disruptor". These synthetic chemicals mimic naturally occurring endocrines by binding to endocrine receptors. This has been clearly demonstrated. It is disingenuous to say that "there is no known mechanism" in the literature. There have been thousands of studies and there is a clear scientific consensus.

  • I like L4D and Resident Evil as much as the next person but this is an article about growth hormones, the cattle industry and how the byproducts don't dissipate as once believed. I guess if you want hits, just add the word zombie to a page.

  • Klingon or Romulan?

    In all seriousness though, this is something that demands further investigation. Going skinny dipping, only for her to later turn over and say "no, I've got a headache" is a PITA at best.

    • If your partner is drinking enough of the runoff to immediately change her (?) libido, both you and your partner have other, more pressing problems to worry about.

  • I can think of two really simple solutions right off the top of my head. Pour lots of bleach in the water, or place bright full-spectrum lights around the lake to shine all night. Duh!

  • Makes you wonder (Score:5, Interesting)

    by drinkypoo ( 153816 ) <drink@hyperlogos.org> on Friday September 27, 2013 @10:15AM (#44971161) Homepage Journal

    Kind of makes you wonder if the breakdown products from this stuff can get into your body separately, and then combine there. Well, it makes me wonder. Maybe that's because I'm not a biologist, or maybe it's because I'm a pessimist.

  • Sunlight and night? (Score:4, Informative)

    by TheCarp ( 96830 ) <sjc AT carpanet DOT net> on Friday September 27, 2013 @10:24AM (#44971273) Homepage

    Well here is what gets me... if they break down in sunlight, but then recombine without the light, well.... natural bodies of water tend not to be terribly clear. You don't have to go down far to not find all that much light, especially if the area itself isn't in direct sunlight....

    So its likely that in many place, it doesn't even take "night", breakdown is likely only happening within a short distance of the surface.

    • Ultraviolet, the real chemical buster of our sun's output has substantially better penetrating power than visible light.

      • Except in water.
      • Don't some water treatment facilities pass water through ultraviolet light? After all of that processing in the water company's equipment would those chemicals still re-combine [say like when it is in the underground pipes]?
      • Ultraviolet, the real chemical buster of our sun's output has substantially better penetrating power than visible light.

        Except it doesn't. Visible light can penetrate meters into water, but almost all ultraviolet is absorbed in the first foot and converted into heat. The rest is absorbed in the second foot of water. Ultraviolet is also absorbed efficiently by water vapor in the atmosphere. The water molecules then emit infrared radiation.

C'est magnifique, mais ce n'est pas l'Informatique. -- Bosquet [on seeing the IBM 4341]

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