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Widely Used Antibacterial Chemical May Impair Muscle Function

Posted by Soulskill on from the it-wasn't-me,-it-was-the-one-armed-antibacterial-chemical dept.

New submitter daleallan writes "Triclosan, which is widely used in consumer handsoaps, toothpaste, clothes, carpets and trash bags, impairs muscle function in animal studies, say researchers at UC Davis (abstract). It slows swimming in fish and reduces muscle strength in mice. It may even impair the ability of heart muscle cells to contract. The chemical is in everyone's home and pervasive in the environment, the lead researcher says. One million pounds of Triclosan is produced in the U.S. annually and it's found in waterways, fish, dolphins, human urine, blood and breast milk. The researchers say their findings 'Call for a dramatic reduction in use.' It's in my Colgate Total toothpaste, and in fact, preventing gingivitis is the only use that may be worthwhile, although this makes me think twice about continuing to brush with it." This isn't the first time Triclosan has been in the news over safety concerns.

18 of 252 comments (clear)

  1. Who would have thought... by korgitser · · Score: 5, Funny

    ... that a substance used to harm life would harm life?

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    FCKGW 09F9 42
    1. Re:Who would have thought... by HungryHobo · · Score: 5, Informative

      there's lots of things which harm only some kinds of life.

      Your eyes are protected by Lysozyme: enzymes which attack bacteria but it doesn't harm your eyes.

      Lots of things are harmful to one organism and not another: Theobromine is deadly to dogs but fairly harmless to us except in extreme quantities because we have enzymes which can handle it.

      Oxygen will kill many types of bacteria but we need it to live.

      Many anti-bacterials are simply far far far less toxic to us than to bacteria so it's not that surprising but it makes an awful rule of thumb.

    2. Re:Who would have thought... by Rei · · Score: 5, Funny

      Hey, I've been around Slashdot long enough to learn that plutonium in baby food is healthy for babies, and anyone who says otherwise is a socialist hippie bent on destroying the global economy. ;)

      --
      We're practicing our labials.
    3. Re:Who would have thought... by HungryHobo · · Score: 5, Funny

      Atomic oxygen is: fortunatly we have the enzyme Catalase in our cells to turn hydrogen peroxide into O2 and water rather than Atomic oxygen and water.

      Tell you what: I'll sit in a chamber filled with 100% pure oxygen for an hour and you do the same in a chamber filled with 100% pure nitrogen then we compare notes.

    4. Re:Who would have thought... by David+Hume · · Score: 5, Insightful

      Nassim Nicholas Taleb, the author of The Black Swan and Fooled by Randomness, has a book chapter coming out that addresses this danger. Prof. Teleb's draft chapter on Medicine, Convexity, and Opacity from his upcoming book, Antifragile: Things That Gain from Disorder, can be found at:

      http://www.fooledbyrandomness.com/medicine.pdf

      While the entire chapter is worth a read, at page 389 he observes:

      The “do you have evidence” fallacy, mistaking evidence of no harm for no evidence of harm, is similar to the one of misinterpreting NED (no evidence of disease) for evidence of no disease. This is the same error as mistaking absence of evidence for evidence of absence, the one that tends to affect smart and educated people, as if education made people more confirmatory in their responses and more liable to fall into simple logical errors.

      That may have been the case here. That is, for years no evidence of harm was mistaken for evidence of no harm.

      More generally, Prof. Taleb argues at page 376:

      Simple, quite simple decision rules and heuristics emerge from this chapter. Via negativa, of course (by removal of the unnatural): resort to medical techniques when the health payoff is very large (say, saving a life) and visibly exceeds its potential harm, such as incontrovertibly needed surgery or lifesaving medicine (penicillin). It is the same as with government intervention. This is squarely Thalesian, not Aristotelian (that is, decision making based on payoffs, not knowledge). For in these cases medicine has positive asymmetries —convexity effects— and the outcome will be less likely to produce fragility. Otherwise, in situations in which the benefits of a particular medicine, procedure, or nutritional or lifestyle modification appear small—say, those aiming for comfort—we have a large potential sucker problem (hence putting us on the wrong side of convexity effects).

      --
      Only Women Bleed (Sex, Sharia remix)
    5. Re:Who would have thought... by rayzat · · Score: 5, Funny

      Probably dead already. Zombies posting AC in order to hide the coming surge.

    6. Re:Who would have thought... by pushing-robot · · Score: 5, Interesting

      Lots of things are harmful to one organism and not another: Theobromine is deadly to dogs but fairly harmless to us except in extreme quantities because we have enzymes which can handle it.

      Sorry to nitpick, but that's not really the best example. The LD50 for theobromine poisoning in dogs is 300mg/kg, around 1/3 that of humans. The TDLO (lowest amount required for symptoms) in dogs is 16mg/kg, about 2/3 that of humans. They really aren't that different from us.

      A 3kg chihuahua could eat a standard-size (43g) Hershey's milk chocolate bar and be completely asymptomatic. To reach its LD50, that chihuahua would have to eat around 15 chocolate bars. Of course, most dogs are much heavier than 3kg and have a similarly higher tolerance for theobromine: If a dog weighed as much as a typical human (let's say 75kg), it could eat 25 chocolate bars without any harmful effect.

      It's important to realize that dogs are opportunistic and will overeat if given the opportunity. Most breeds are also much smaller than humans. Stories of theobromine poisoning typically come from dogs who discovered a cache of chocolate candies and consumed an enormous amount compared to their body weight.

      But as long as you maintain some level of portion control, there's really nothing wrong with giving them a normal amount of chocolate in their diet. Just be careful with purer forms of chocolate—dark chocolate can have three times and raw unsweetened chocolate can have ten times as much theobromine as normal chocolate candy.

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      How can I believe you when you tell me what I don't want to hear?
  2. Triclosan is not the only drug found in waterways by Taco+Cowboy · · Score: 5, Informative

    Need to stress this, Triclosan is not the only drug found in waterways

    A lot of other substances that human being are using ended up in waterways and they are having all types of side effects on ecology around us

    I read an article about 10 years ago that nano-silver particles that we human are using - to kill bacteria, -somehow entered the waterways and end up killing a lot of microbial lifeforms, and the chain reaction (according to the articles that i read, can't find the links to them anymore, sorry) was worrying
     

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    Muchas Gracias, Señor Edward Snowden !
  3. What was the dose? by sirwired · · Score: 5, Insightful

    I can certainly dose any given collection of animals with nearly any given chemical in a fashion that will kill them (either quickly or slowly, depending on the particular substance.) I can also dose them with an utterly harmless dose of the most toxic and horrible poisons known to mankind and the animal will live. This applicable to everything from water or oxygen to nasty organic or radiologic stuff.

    In the end, it all comes down to the dose. Was the dose these animals were given at all representative of the dosing received by a person using triclosan-based products? (Or animals absorbing triclosan in the environment?) Would have been nice if that press release had mentioned it. Since it didn't, I can guess that the dose is utterly ridiculous.

    1. Re:What was the dose? by CSMoran · · Score: 5, Informative
      If you click to read the abstract (I know, bad etiquette), you'll find that it

      acutely depresses hemodynamics and grip strength in mice at doses 12.5 mg/kg

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      Every end has half a stick.
    2. Re:What was the dose? by FirephoxRising · · Score: 5, Informative

      You should URGENTLY call poisons information if someone eats significant amounts of toothpaste. The Fluoride can and has killed people.

    3. Re:What was the dose? by Darth_brooks · · Score: 5, Insightful

      "If a small kid ate an entire tube, it'd be time to call poison control and induce vomiting from the sounds of it."

      Which you'd already have to do since most toothpaste contains Fluoride which, in addition to ruining the purity of our essence, isn't the healthiest stuff on earth to begin with.

      Worrying about triclosan in toothpaste is a bit like worrying about the mercury content of your cyanide.

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      There are some people that if they don't know, you can't tell 'em.
  4. Look at the dosing! by sowalsky · · Score: 5, Insightful

    The experiments in mice were performed at 12.5mg/kg, which would be (for the average 65-kg human) a shocking 812.5mg of Triclosan. If your standard amount of handsoap and toothpaste is 2ml that's like brushing your teeth with a 1/3 solution of triclosan and swallowing it.

    Like most of the research in PNAS this was not subjected to the high level of peer review expected in most scholarly journals and this paper got through without regard to its relevance and real-world significance.

    At a high enough dose, caffeine causes cancer in lab animals. But not at the doses even Slashdotters consume.

  5. Hmm... I missed that, but it appears to be high by sirwired · · Score: 5, Interesting

    12.5 mg/kg! Holy cow! This is ridiculously in excess of any conceivable dose of Triclosan you could get unless you are an utterly unprotected employee of a Triclosan-using factory.

  6. does it really affect people adversely? by MassiveForces · · Score: 5, Interesting

    For one thing, its reversible. Wears off after 60 mins in mice at the dose they were using. Hey that might even mean less free radicals which cause aging. Second, humans aren't going to notice the effects at the doses they receive, otherwise we would have seen it in factory workers that produce triclosan already. So nobody should be alarmed at least, unless maybe it impairs salmon swimming upstream to reproduce.

  7. Re:It's just random use of antibiotics. by 12WTF$ · · Score: 5, Funny

    Some of the healthiest guys are sewer workers, they rarely take a sick day, because their immune systemsare so strong, since they are constantly fighting off bacteria.

    But their breath is knock down nasty and their farts are room clearing because sewage workers' internal bio flora has a larger population of anaerobic and methanogenic bacteria. Apart from that they are really nice guys.

    --
    Cryonics - Keep cool and carry on.
  8. Re:Can't stand your neighbor's dog yepping ? by Anonymous Coward · · Score: 5, Informative

    You would be better off giving it a grape or an onion. Chocolate is fairly weak in killing a dog than that of cocoa itself. An onion actually causes the blood cells in a dog to "pop" which means a deader dog in a shorter time.

  9. Re:Evolution by queazocotal · · Score: 5, Informative

    In context.
    http://www.ncbi.nlm.nih.gov/pubmed/22885664

    Urinary levels of bisphenol A, triclosan and 4-nonylphenol in a general Belgian population.

    'Geometric mean concentration was determined for bisphenol A at 2.55ug/l and for triclosan at 2.70ug/l'

    Now, Triclosans molar mass is around 300.
    0.52uMol/l is therefore 300 times this - 150ug/l.
    So, this is lots higher - 50 times - that in the general population.
    (Assuming urine and blood are of similar concentration, I can find no papers on this in 2 mins)

    However, 50* is not a stupid amount to exceed dosages by, especially given that it's likely that some humans will exceed the average by at least 5 times.