Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Medical Vibroacoustic Disease

  1. Oct 22, 2007 #1
    There are many articles on PubMed in regard to what is termed Vibroacoustic Disease. The majority of human studies appear to center around aerospace workers and long term exposure to LFN (low frequency noise).

    Is this phenomena recognized as valid in the scientific community, or is the jury still out?
     
  2. jcsd
  3. Oct 22, 2007 #2
    Which journals carry the papers? Are those journals peer-reviewed?
     
  4. Oct 23, 2007 #3
    I can't get there from here at the moment to review them. <banging keyboard on desk, searching for a mallet>
     
  5. Oct 23, 2007 #4

    jim mcnamara

    User Avatar
    Science Advisor
    Gold Member

    Short answer: yes peer reviewed
    Prog Biophys Mol Biol. 2007 Jan-Apr;93(1-3):256-79.
    Alves-Pereira M, Castelo Branco NA.
    ERISA, Lusofona University, Avenida Primeiro de Maio, No. 27, 5B, Costa da Caparica, 2825 397 Lisbon, Portugal. m.alvespereira@gmail.com

    At present, infrasound (0-20 Hz) and low-frequency noise (20-500 Hz) (ILFN, 0-500 Hz) are agents of disease that go unchecked. Vibroacoustic disease (VAD) is a whole-body pathology that develops in individuals excessively exposed to ILFN. VAD has been diagnosed within several professional groups employed within the aeronautical industry, and in other heavy industries. However, given the ubiquitous nature of ILFN and the absence of legislation concerning ILFN, VAD is increasingly being diagnosed among members of the general population, including children. VAD is associated with the abnormal growth of extra-cellular matrices (collagen and elastin), in the absence of an inflammatory process. In VAD, the end-product of collagen and elastin growth is reinforcement of structural integrity. This is seen in blood vessels, cardiac structures, trachea, lung, and kidney of both VAD patients and ILFN-exposed animals. .... <snip>

    --------------

    Which does not leave me with any feeling that the condition is understood all that well - it's more of a clinical/semi-pathological description than anything else. IMO.

    Considering that some animals across major taxonomic groups have generated and used infrasound to communicate - modern elephants are one - leaves me even more puzzled about this condition. Since I know a large number of aerospace guys, I think there may be a fast food - infrasound interaction ( joke, sort of).

    I vote for 'up in the air'.
     
  6. Oct 23, 2007 #5
    Jim, thank you for the response, and sorting through the journals.

    Can you explain your thoughts about the use of infrasound by animals to communicate in relation to being puzzled?
     
    Last edited: Oct 23, 2007
  7. Oct 24, 2007 #6
    That Castelo Branco's name appears on most of the papers listed at PubMed. He and his colleages are clearly specializing in studying this condition and are probably the source of the concept. Unless a lot of non-associated researchers study this independently of that core group then we're probably reading stuff that hasn't been much challenged or honed.
     
  8. Oct 24, 2007 #7

    jim mcnamara

    User Avatar
    Science Advisor
    Gold Member

    Elephants generate 18-20Hz sounds which carry incredible distances, for example.
    If longterm exposure to 18-20 Hz sound did systemic cell damage, why would several distinct unrelated taxa be able to generate those sounds over a long lifetime without doing themselves damage?

    As a general observation, elephant reproductive cycles are long, so Natural Selection would not favor those animals making infrasound unless making those sounds really outwieghed the damage. It would be analogous to kids who make loud noises cause cell damage to important organs in their abdomen. Thus making sure they do not reproduce longterm as effectively as quiet kids.

    In other words, see Zooby's post.

    Aerospace workers are exposed to odd metals, like titanium, beryllium and even odder chemicals used for metal finishing, EMF supression in wires, etc. If they are like the guys at the restuarant next to Eclipse aviation where I eat lunch, then they are smart folks but could care less about metals exposure. Exposure to chemicals/metals like those is far more likely to cause cell damage than sound that does not affect animals "living" in it, IMO. I saw nothing to discount other possible sources of the condition.

    I do not doubt the symptoms/pathologies observed clinally, just the probable etiology.
     
  9. Oct 24, 2007 #8
    I poked through some articles and the damage isn't laid to infrasound, per se, but to very long term exposure (years) to high intensity infrasound such as you'd recieve working around jets. Casual logic leads me to observe that, while elephants are large, there is no part of them dedicated to generating infrasound which is as large as a jet engine.

    And that's a sound argument if I ever heard one ;)
     
  10. Oct 24, 2007 #9

    jim mcnamara

    User Avatar
    Science Advisor
    Gold Member

    I understand. But I recall the (I should not bring this up...) research published by Swedish researchers statistically linking certain leukemias with people living longterm very close to transmission lines.

    It caused an uproar. Later research by others waffled the results as I recall.

    For a class I taught, I once did a stat correlation between the consumption of checkerboard ice cream (remember that?) in NJ, based on sales volume and the manufacturing volume of electric carving knives in a plant in NJ. Got a really high Pearson r value, of like .96 for monthly data from a period of four years.

    That means 97.5% of the variance of ice cream production can be "accounted for" by changes in knife production and the linear relationship between production levels of knives and ice cream. It could not possibly be wrong? Correct me where I went wrong.

    Now, that's a sweet (sharp?) argument....
     
  11. Oct 24, 2007 #10
    Your study is brilliant!

    However, there is some experimentation to back up these authors' claims of a link:

    http://www.ncbi.nlm.nih.gov/sites/e...ez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum

    As soon as they hear any objections about the elephants I suppose they'll be pressured into accounting for them not being affected. It could be they are, but have evolved compensatory mechanisms; or maybe their thick, wrinkly hide is all about dampening the full body exposure, and so on.

    Your original point, that there are lots of things in that industry that could be causing damage, is a good one and some good evidence has to be offered to single out this cause over others.
     
  12. Oct 24, 2007 #11
    Okay, we know that those people get them but what does it do to you?
     
  13. Oct 25, 2007 #12

    jim mcnamara

    User Avatar
    Science Advisor
    Gold Member

    For me. Which one: fast food, elephant infrasound, or aerospace occupational hazards.
    I've discovered the Fried Chicken and coleslaw diet mediates against the effects of all three.
    Fried Chicken is a food group, not fast food, by the way....
     
    Last edited: Oct 25, 2007
  14. Oct 27, 2007 #13

    Moonbear

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Calling it "noise" may be misleading here, as it implies its the sound at issue. My understanding of the disorders arising from those low frequency vibrations is from the mechanical vibration, which requires a certain amplitude to the vibration as well. We had a speaker from NIOSH give a seminar on that fairly recently, and she was referring to it in context of those using equipment such as power drills and jackhammers all day (so, I'm going to just relate what I recall from the seminar). The vibrations transmitted through the tools to the workers' hands were the source of the problems (she uses rats as a model for studying this...setting them up with their tails on a shaker table to look at the effect of just vibrating their tails on the whole body physiology). What was particularly interesting to me is that it's not just a mechanical damage, although there was a mechanical source. The patients experiencing this do not just have injury to their hands and arms from the vibration, but even develop neuropathies and cardiovascular problems in distant organs or feet, etc. The symptoms are very similar to diabetic neuropathy, and it is even possible that some workers who happen to have diabetes end up misdiagnosed as diabetic neuropathy when diabetes is not the primary cause. Anyway, the main point was really that the mechanism is NOT well understood beyond that of the mechanical stresses to the body at the site of initial injury. What is going on physiologically to effect symptoms in other parts of the body remains unknown.

    Right now, the main status of the field of study seems to be focused on occupational exposures and determining how long a worker can safely be exposed to such vibrations before needing to take breaks, how long those breaks should be, and what are the early signs of the disorder to determine it is time to stop performing that job permanently. This is of primary importance in preventing the disorder in the first place. The secondary focus is on understanding the biology behind the disorder in order to treat those who have already developed it...but this is still very limited, and it seems researchers are just searching to even find a starting point to understand this problem.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Vibroacoustic Disease
  1. Checking disease (Replies: 2)

  2. Alzheimer's disease (Replies: 6)

  3. Genetic Diseases (Replies: 3)

  4. Infectious Diseases (Replies: 6)

Loading...