{"id":10821,"date":"2010-11-08T14:54:01","date_gmt":"2010-11-08T19:54:01","guid":{"rendered":"https:\/\/www.windturbinesyndrome.com\/static\/static\/?p=10821"},"modified":"2012-01-25T05:06:40","modified_gmt":"2012-01-25T10:06:40","slug":"wind-turbines-infrasound-and-health-effects","status":"publish","type":"post","link":"https:\/\/www.windturbinesyndrome.com\/static\/2010\/wind-turbines-infrasound-and-health-effects\/","title":{"rendered":"Wind turbines, infrasound, and health effects"},"content":{"rendered":"<div class=\"pf-content\"><h4>&#8220;Infrasound: Your ears &#8216;hear&#8217; it but they don\u2019t tell your brain&#8221;<\/h4>\n<p>\u2014<a title=\"Dr. Alec Salt\" href=\"http:\/\/aladdin.wustl.edu\/oto\/otoweb.nsf\/RA\/28817C798ADCB4DA8625734C006914DF?OpenDocument&amp;C=Research\" target=\"_blank\">Alec Salt, PhD, Department of Otolaryngology, Washington University School of Medicine<\/a>, St. Louis, Missouri, USA, at the &#8220;Symposium on Adverse Health Effects of Industrial Wind Turbines,&#8221; Picton, Ontario, October 29-31, 2010. \u00a0(See the <a title=\"Cochlear Fluids Research Lab\" href=\"http:\/\/oto2.wustl.edu\/cochlea\/\" target=\"_blank\">Cochlear Fluids Research Laboratory<\/a> site, and &#8220;<a title=\"website\" href=\"http:\/\/oto2.wustl.edu\/cochlea\/windmill.html\" target=\"_blank\">Responses of the Ear to Infrasound and Wind Turbines<\/a>.&#8221;<\/p>\n<p><span style=\"color: #999999;\">Highlights:<\/span><\/p>\n<p style=\"padding-left: 30px;\"><span style=\"color: #999999;\">&#8220;Physiologic pathway exists for infrasound at levels that are not heard to affect the brain. The idea that infrasound effects can be dismissed because they are inaudible is\u00a0<em>incorrect<\/em>.&#8221;<\/span><\/p>\n<p style=\"padding-left: 30px;\"><span style=\"color: #999999;\">&#8220;A-weighted measurements tell you NOTHING about infrasound content.&#8221;<\/span><\/p>\n<p style=\"padding-left: 30px;\"><span style=\"color: #999999;\">&#8220;A-weighted spectra totally misrepresent the effects of wind turbine noise (that includes infrasound components) on the ear.&#8221;<\/span><\/p>\n<p style=\"padding-left: 30px;\"><span style=\"color: #999999;\">&#8220;A-weighted level readings (e.g., 42 dBA) are totally meaningless for assessing whether turbine noise is affecting the ear.&#8221;<\/span><\/p>\n<p><span style=\"color: #c0c0c0;\"><a title=\"Salt PowerPoint slides\" href=\"https:\/\/www.windturbinesyndrome.com\/static\/wp-content\/uploads\/2010\/11\/Salt-PowerPoint.pdf\" target=\"_blank\">Click here to download a PDF of Dr. Salt&#8217;s PowerPoint slides, from which the following text was taken.<\/a><\/span><\/p>\n<p><span style=\"color: #ffffff;\">\u00b7<\/span><br \/>\n<!--more-->Wind turbines generate infrasound.<\/p>\n<p>Wind turbine infrasound is at levels that cannot be heard.<\/p>\n<p>Widely cited interpretations:<\/p>\n<ul>\n<li>\u201cIf you cannot hear a sound \u2026 it does not affect you\u201d\u2014Leventhall G. What is infrasound? P<em>rogress in Biophysics and Molecular Biology<\/em> 2007; 93:130\u2013137<\/li>\n<li>\u201cInfrasound is negligible\u201d\u2014DELTA. <em>Low Frequency Noise from Large Wind Turbines<\/em> 2008<\/li>\n<li>\u201cInfrasound \u2026 is below the audible threshold and of no consequence\u201d\u2014Leventhall G. <em>Canadian Acoustics<\/em> 2006; 34:29-36.<\/li>\n<\/ul>\n<p>This logic seems to be applied only to hearing. Consider other senses:<\/p>\n<ul>\n<li><span style=\"color: #ff0000;\">Taste<\/span>: If you can\u2019t taste it, it can\u2019t affect you? Can you taste salmonella?<\/li>\n<li><span style=\"color: #ff0000;\">Smell<\/span>: If you can\u2019t smell it, it can\u2019t affect you? Try breathing pure CO or CO\u2082<\/li>\n<li><span style=\"color: #ff0000;\">Sight<\/span>: If you can\u2019t see it, it can\u2019t affect you? Photokeratitis, \u201csnow blindness\u201d, \u201cwelder\u2019s flash\u201d, cataracts, sunburn: Ultraviolet (UV) light is invisible; even though you can\u2019t see it, UV does affect you. UV can harm you.<\/li>\n<\/ul>\n<p>\u201cIf you can\u2019t hear it, it can\u2019t affect you\u201d is only true:<\/p>\n<ul>\n<li>if no other part of the ear is more sensitive than hearing, and<\/li>\n<li>if no other part of the body is more sensitive than hearing \u2026<\/li>\n<li>and I will show this is <em>not <\/em>true.<\/li>\n<\/ul>\n<p>Infrasound at moderate levels is detected by the ear.<\/p>\n<p>Infrasound at levels generated by turbines affect the ear.<\/p>\n<p>Vibrations cause a bending of the ear\u2019s sensory hairs. The inner hair cells are connected to auditory (type I) nerve fibers that send signals to the brain. You \u201chear\u201d with your inner hair cells.<\/p>\n<p>Inner (IHC) and outer (OHC) hair cells respond differently as sound frequency is changed. IHC respond to velocity. OHC respond to displacement. OHC respond at approximately 40 dB below IHC sensitivity at 2 Hz.<\/p>\n<p>Outer hair cells will be stimulated by wind turbine noise. \u00a0(See graph, below.)<\/p>\n<p><a href=\"https:\/\/www.windturbinesyndrome.com\/static\/wp-content\/uploads\/2010\/11\/Salt-graph-561x435.jpg\"><img loading=\"lazy\" class=\"aligncenter size-full wp-image-10823\" src=\"https:\/\/www.windturbinesyndrome.com\/static\/wp-content\/uploads\/2010\/11\/Salt-graph-561x435.jpg\" alt=\"\" width=\"561\" height=\"435\" srcset=\"https:\/\/www.windturbinesyndrome.com\/static\/wp-content\/uploads\/2010\/11\/Salt-graph-561x435.jpg 561w, https:\/\/www.windturbinesyndrome.com\/static\/wp-content\/uploads\/2010\/11\/Salt-graph-561x435-300x232.jpg 300w\" sizes=\"(max-width: 561px) 100vw, 561px\" \/><\/a><\/p>\n<p><span style=\"text-decoration: underline;\">Outer hair cells do not just detect sound<\/span>:<\/p>\n<p>For low-amplitude high frequencies, OHC elongate when hairs are bent outwards, which makes stimulus greater for IHC (amplifies signal).<\/p>\n<p>Amplifier becomes less effective (less necessary) for higher level sounds, ineffective about 40 dB above threshold\u00a0(Reichenbach T, Hudspeth AJ. <em>Proc Natl Acad Sci<\/em> U.S.A. 2010)<\/p>\n<p>High-Frequency stimulus: OHC elongate; Vibration amplitude at the IHC is amplified.<\/p>\n<p><em>At very low frequencies, we know that bending the hairs laterally causes OHC to contract<\/em>.<\/p>\n<p>Infrasound stimulus: OHC contract; Vibration amplitude at the IHC is reduced.<\/p>\n<p>OHC are detecting low-level infrasound and actively canceling it for the IHC.<\/p>\n<p>Physiologic pathway exists for infrasound at levels that are not heard to affect the brain. The idea that infrasound effects can be dismissed because they are inaudible is <em>incorrect<\/em>.<\/p>\n<p>Infrasound =&gt; OHC =&gt; (via type II nerve fibers) subconscious brain: ear fullness, ear pressure, discomfort, alerting\/sleep disturbance<\/p>\n<p>A-weighting corrects a sound measurement to represent what is <em>heard<\/em>, based on the human audibility (40 phon) curve. At 1 Hz, \u2212148 dB correction, equivalent to dividing by 25 million.<\/p>\n<p>Effect of A-weighting wind turbine noise: Massive (140 dB) de-emphasis of infrasound component. A-weighting may represent what you hear\u2014but hearing does not give a reliable indication of whether the infrasound is affecting your ears.<\/p>\n<p>\u201cA-weighting\u201d principle applied to UV light is equivalent to adjusting sunlight spectrum for what is visible and then saying: \u201cThere is nothing here that can harm you. You don\u2019t need sunscreen. You don\u2019t need sunglasses. Go spend all day laying out in the sun.\u201d This approach isn\u2019t rational when applied to light, so why do we accept similar logic applied to sound?<\/p>\n<p>Measuring visible light (e.g., photographs) tells you NOTHING about UV content. Similarly, A-weighted measurements tell you NOTHING about infrasound content.<\/p>\n<p>A-weighted spectra totally misrepresent the effects of wind turbine noise (that includes infrasound components) on the ear.<\/p>\n<p>A-weighted level readings (e.g., 42 dBA) are totally meaningless for assessing whether turbine noise is affecting the ear.<\/p>\n<p>Documenting Wind Turbine Sound<\/p>\n<ul>\n<li>Most video cameras do not record the infrasound component of wind turbine noise.<\/li>\n<li>Speaker systems in TVs and computers cannot play back the infrasound component.<\/li>\n<li>Even if they did\u2014you can\u2019t hear it!<\/li>\n<li>Video recordings of wind turbines give no indication of the infrasound level being produced.<\/li>\n<li>Infrasound can only be measured with specialized instrumentation capable of detecting sounds down to approximately 1 Hz.<\/li>\n<\/ul>\n<p>G-weighting weights infrasound components (excluding higher frequencies) according to human sensitivity curve.<\/p>\n<p>G-weighted turbine measurements: For most of these conditions, the ear will be stimulated by the turbine noise. (Jakobsen J. Infrasound emission from wind turbines. <em>Journal of Low Frequency Noise Vibration and Active Control<\/em> 2005; 24:145-155.)<\/p>\n<p><span style=\"text-decoration: underline;\">Other ways that infrasound could affect the ear<\/span>:<\/p>\n<p>Stimulation of vestibular hair cells (saccule, utricle).<\/p>\n<ul>\n<li>Vestibular hair cells are \u201ctuned\u201d to infrasonic frequencies.<\/li>\n<li>No-one has ever measured sensitivity to acoustic infrasound.<\/li>\n<li>Symptoms: unsteadiness, queasiness<\/li>\n<\/ul>\n<p>Disturbance of inner ear fluids (e.g. endolymph volume).<\/p>\n<ul>\n<li>Low-frequency sound at non-damaging levels induces endolymphatic hydrops (a swelling of one of the fluid spaces).<\/li>\n<li>Infrasound does affect endolymph volume\u2014it is the basis of a treatment for hydrops (M\u00e9ni\u00e8re\u2019s disease).<\/li>\n<li>No one has ever measured what level of infrasound causes hydrops.<\/li>\n<li>Symptoms: ear fullness, unsteadiness, tinnitus<\/li>\n<\/ul>\n<p>Infrasound\u2014affected structures and long-term exposure effects, ranked by sensitivity:<\/p>\n<ol>\n<li>Outer hair cells \u2014 \u201cOverworked, tired, irritated\u201d OHC, type II fiber stimulation<\/li>\n<li>Inner ear fluid homeostasis \u2014 Volume disturbance, endolymphatic hydrops<\/li>\n<li>Saccular hair cells \u2014 Stimulation<\/li>\n<li>Other, non-ear, receptors \u2014 Stimulation<\/li>\n<li>Inner hair cells\/hearing \u2014 None<\/li>\n<\/ol>\n<p>Sensitivity and sensations remain to be quantified: ear pressure or fullness, discomfort, arousal from sleep; ear fullness, tinnitus, unsteadiness; unsteadiness; stress, anxiety.<\/p>\n<p>\u201cWind Turbine Syndrome\u201d \u2014 You cannot hear what causes the symptoms!<\/p>\n<p><em>We need more research to define the sensitivity of these processes<\/em>.<\/p>\n<p>Sounds you cannot hear \u2026<\/p>\n<ul>\n<li>can affect you.<\/li>\n<li>can disturb you.<\/li>\n<li>can harm you.<\/li>\n<li>can cause disease: auditory and balance disorders, effects of sleep deprivation are serious (hypertension, diabetes, mortality).<\/li>\n<\/ul>\n<p><span style=\"text-decoration: underline;\">Conclusion and Recommendations<\/span><\/p>\n<p><em>For years, people have been told that infrasound you cannot hear cannot affect you. This is completely wrong<\/em>.<\/p>\n<p>Because the inner ear <em>does <\/em>respond to infrasound at levels that are not heard, people living near wind turbines are being put at risk by infrasound effects on the body that no one presently understands.<\/p>\n<p>Until a scientific understanding of this issue is established we should not be dismissing these effects, but need to be erring on the side of caution.<\/p>\n<p>For industrial turbines a cautious approach could require :<\/p>\n<ul>\n<li>setbacks of at least 2 kilometers (1.25 miles).<\/li>\n<li>in-home monitoring of both A-weighted (audible) and G-weighted (infrasound) noise levels 24 hours\/day for all dwellings within 2 miles.<\/li>\n<li>health monitoring studies for those living within 2 miles (with consent).<\/li>\n<\/ul>\n<p><em>Finally <\/em>\u2026<\/p>\n<p>We need to stop ignoring the infrasound component of wind turbine noise and find out why it bothers people!<\/p>\n<p>Wind turbine noise is <em>not <\/em>comparable to the rustling of leaves.<\/p>\n<p><span style=\"color: #c0c0c0;\">Editor&#8217;s note: \u00a0Our appreciation to <a title=\"website\" href=\"http:\/\/www.wind-watch.org\/documents\/infrasound-your-ears-hear-it-but-they-dont-tell-your-brain\/\" target=\"_blank\">National Wind Watch<\/a> for re-formatting Dr. Salt&#8217;s talk in a Web-friendly manner.<\/span><\/p>\n<\/div>","protected":false},"excerpt":{"rendered":"<p>&#8220;Infrasound: Your ears &#8216;hear&#8217; it but they don\u2019t tell your brain&#8221; \u2014Alec Salt, PhD, Department of Otolaryngology, Washington University School of Medicine, St. Louis, Missouri, USA, at the &#8220;Symposium on Adverse Health Effects of Industrial Wind Turbines,&#8221; Picton, Ontario, October 29-31, 2010. \u00a0(See the Cochlear Fluids Research Laboratory site, and &#8220;Responses of the Ear to Infrasound and Wind Turbines.&#8221; Highlights: &#8220;Physiologic pathway exists for infrasound at levels that are not heard to affect the brain. The idea that infrasound effects can be dismissed because they are inaudible is\u00a0incorrect.&#8221; &#8220;A-weighted measurements tell you NOTHING about infrasound content.&#8221; &#8220;A-weighted spectra totally misrepresent the effects of wind turbine noise (that includes infrasound components) on the ear.&#8221; &#8220;A-weighted level readings (e.g., 42 dBA) are totally meaningless for assessing whether turbine noise is affecting the ear.&#8221; Click here to download a PDF of Dr. Salt&#8217;s PowerPoint slides, from which the following text was taken. \u00b7<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[163,16],"tags":[],"_links":{"self":[{"href":"https:\/\/www.windturbinesyndrome.com\/static\/wp-json\/wp\/v2\/posts\/10821"}],"collection":[{"href":"https:\/\/www.windturbinesyndrome.com\/static\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.windturbinesyndrome.com\/static\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.windturbinesyndrome.com\/static\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.windturbinesyndrome.com\/static\/wp-json\/wp\/v2\/comments?post=10821"}],"version-history":[{"count":0,"href":"https:\/\/www.windturbinesyndrome.com\/static\/wp-json\/wp\/v2\/posts\/10821\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.windturbinesyndrome.com\/static\/wp-json\/wp\/v2\/media?parent=10821"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.windturbinesyndrome.com\/static\/wp-json\/wp\/v2\/categories?post=10821"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.windturbinesyndrome.com\/static\/wp-json\/wp\/v2\/tags?post=10821"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}