Response to Prof Leventhall’s Comments at Australian Federal Senate Inquiry
RESPONSE TO PROFESSOR LEVENTHALL’S COMMENTS TO AUSTRALIAN FEDERAL SENATE INQUIRY INTO EXCESSIVE NOISE FROM WIND FARMS BILL
November 27, 2012
The following comments are made in response to a number of assertions and comments Professor Leventhall has made, in response to my submission to the above inquiry, which are either untrue, or in conflict with previous public statements, documents or court evidence given by Professor Leventhall, or which are disputed by a number of his acoustic peers with recent relevant field experience.
Firstly, Professor Leventhall has stated in his comment in paragraph No 4 of his response to the senate concerning the issue I raised about the 2003 DEFRA report and the exclusion of it from the NHMRC’s Rapid Review, that
“I was the author of the 2003 report, reference 7 of Dr Laurie’s submission. LFN and Infrasound from wind turbines were not considered in the report as they were not believed to be a problem”
However, this is inconsistent with what the 2003 DEFRA report actually states, which Leventhall wrote 7 years earlier, on page 54, in section 13.2 with the subtitle of Effects on humans:
“Infrasound exposure is ubiquitous in modern life. It is generated by natural sources such as earthquakes and wind. It is common in urban environments, and as an emission from many artificial sources: automobiles, rail traffic, aircraft, industrial machinery, artillery and mining explosions, air movement machinery including wind turbines, compressors, and ventilation or air-conditioning units, household appliances and some therapeutic devices. The effects of infrasound or low frequency noise are of particular concern because of its pervasiveness due to numerous sources, efficient propagation, and reduced efficiency of many structures (dwellings, walls, and hearing protection) in attenuating low frequency noise compared with other noise”. (Bold is my emphasis)
(The DEFRA Literature Review is downloadable from http://www.wind-watch.org/documents/review-of-published-research-on-low-frequency-noise-and-its-effects/ )
It would appear, therefore, from Professor Leventhall’s comments in 2003, that he did think in 2003 that the effects of infrasound and low frequency noise, from a variety of sources including wind turbines, could cause the health problems he described in that crucially important 2003 DEFRA Literature Review.
There is in addition a very serious issue regarding the text of the paragraph on page 54 of the 2003 DEFRA document. It is almost identical to a paragraph in another document, a peer reviewed published journal article, written 7 years prior to the DEFRA document by different authors. The relevant quote is reproduced in full, below, with the original authors listed, together with the publication. There does not appear to be any attribution of this paragraph in the DEFRA document to the original authors Berglund et al, nor are there quotation marks.
“Low-frequency noise is common as background noise in urban environments, and as an emission from many artificial sources: road vehicles, aircraft, industrial machinery, artillery and mining explosions, and air movement machinery including wind turbines, compressors, and ventilation or air-conditioning units. The effects of low-frequency noise are of particular concern because of its pervasiveness due to numerous sources, efficient propagation, and reduced efficacy of many structures (dwellings, walls, and hearing protection) in attenuating low-frequency noise compared with other noise.” (bold is my emphasis)
B. Berglund, P. Hassmen, and RF Job, “Sources and Effects of Low-Frequency Noise,” Journal of the Acoustical Society of America, vol. 99, no. 5 (May 1996):2985- 3002, Abstract.
The only difference between the two quotes appears to be the addition of the words “infrasound or” to the first part of the second paragraph, which in the DEFRA document reads “The effects of infrasound or low frequency noise….”
The reproduction of this original 1996 paragraph in the 2003 DEFRA document without apparent attribution or referencing raises serious questions of academic and professional probity.
Further examination of the Berglund review makes it very clear that even in 1996 when that paper was published, that leading researchers in this area of community and environmental noise considered that wind turbine low frequency noise was a problem. On page 2987, the authors state:
“Finally, the data on wind turbines indicate that the predominance of low frequency noise is of particular concern for communities living close to wind turbines”
If that was the opinion of Berglund et al in 1996, based on the existing limited data with small wind turbines, it is even more the case now, with even larger more powerful wind turbines being favoured by the wind industry because of their ability to generate more power. “Size matters”, as Professors Moller and Pedersen clearly showed in their peer reviewed published research from 2011, where they stated
“As wind turbines get larger, worries have emerged that the turbine noise would move down in frequency and that the low-frequency noise would cause annoyance for the neighbors. The noise emission from 48 wind turbines with nominal electric power up to 3.6 MW is analyzed and discussed. The relative amount of low-frequency noise is higher for large turbines (2.3–3.6 MW) than for small turbines (< 2 MW), and the difference is statistically significant. The difference can also be expressed as a downward shift of the spectrum of approximately one-third of an octave. A further shift of similar size is suggested for future turbines in the 10-MW range. Due to the air absorption, the higher low-frequency content becomes even more pronounced, when sound pressure levels in relevant neighbor distances are considered. Even when A-weighted levels are considered, a substantial part of the noise is at low frequencies, and for several of the investigated large turbines, the one-third-octave band with the highest level is at or below 250 Hz. It is thus beyond any doubt that the low-frequency part of the spectrum plays an important role in the noise at the neighbors“.
Professors Moller & Pedersen’s paper can be downloaded from http://www.wind-watch.org/documents/low-frequency-noise-from-large-wind-turbines-2/
So, it would appear that not only were there concerns being expressed about the impact of low frequency noise from wind turbines in 1996 by Berglund et al, there were concerns expressed in the DEFRA document about low frequency noise in 2003 by Professor Leventhall himself (albeit with apparently unattributed text from the Berglund document). These concerns would appear to be well founded, given the later Moller and Pedersen research, and because of the global tendency to increasingly use larger wind turbines.
Scientific clinical and acoustic evidence is continuing to raise serious concerns about the adverse health impacts of infrasound and low frequency noise from wind turbines, and includes the acoustic survey and analysis field work being done by Professor Leventhall’s acoustic peers such as James, Bray, Swinbanks, Rand, Ambrose, Thorne and Cooper. Clinical observations and research includes the work of concerned clinicians and other researchers or public health physicians with first hand knowledge of the problems of the residents living near wind turbines such as Harry (UK), Iser (Australia), Pierpont (USA), McMurtry (Ontario), Krogh (Ontario), Shepherd (NZ), Nissenbaum (Maine), Hanning, (UK), Aramini (Ontario), Lynn (Ontario), Johansson (Denmark), Kuck (Germany), Spring (Australia), Mitric-Andjic (Australia), Trask (Australia). Other clinicians who have expressed their concern and said there is an urgent need for research into the reported problems include Dr Owen Black MD, and clinical colleagues in Quebec such as Dr Linda Bernier. The Australian Federal Senate itself recognized the need for urgent research, as a result of the previous Federal Senate inquiry in 2011.
Steven Cooper is an Australian acoustician who has written and spoken publicly about the ethical obligations of acousticians in this area of wind turbine noise, and was the author of a recent technical paper on this topic (downloadable at http://www.acoustics.asn.au/journal/Vol40No2.pdf ). Specifically, the British Institute of Acoustics Code of Conduct states the following:
“All members of the Institute shall at all times:
• so order their conduct as to uphold the dignity and reputation of the profession and of the Institute and of its members and officers
• safeguard the public interest in matters of safety, health and the environment
• exercise their professional skill and judgement to the best of their ability
• discharge their professional responsibilities with integrity, honesty and diligence”
Extract taken from http://http://www.ioa.org.uk/membership/code-conduct
Professor Leventhall goes on to state in paragraph 8 of his response to my submission that “as a Rapid Review, the report cannot be expected to be wide ranging and comprehensive, but has to concentrate on the main points”. It would be reasonable to expect that the “main points” would include as a priority, examining the detailed literature review of the existing scientific research evidence about the adverse health effects of low frequency noise, ie the 2003 DEFRA Literature Review, which Professor Leventhall was the lead author of, which clearly listed wind turbines as a source of both infrasound and low frequency noise. Leaving out this particular literature review from the NHMRC’s 2010 Rapid Review, which he peer reviewed, brings into serious question whether the ethical issues outlined above in the British Institute of Acoustics Code of Conduct have been breached.
Professor Leventhall’s British colleague Dr Malcolm Swinbanks has written a very informative letter in September this year which is self explanatory about information concerning acoustic measurements of wind turbine noise which Professor Leventhall was privy to between 2003 and 2010, and he also makes reference to how Professor Leventhall has previously misrepresented my medical colleague, Dr Pierpont:
“In his 2006 Canadian paper relating to infrasound and wind turbines, Leventhall criticised Dr Nina Pierpont for having referred to the impulsive noise from wind-turbines as “infrasound”, arguing that the relevant paper that she had quoted by G.P. van den Berg did not relate to infrasound at all, but only to dBA levels. In 2003 & 2004, G.P. van den Berg actually published two separate papers, both relating to the specific windfarm in Holland that he (van den Berg) had assessed. The first paper did indeed only relate to dBA levels, but the second paper referred explicitly to low-frequency and infrasound, and described how the turbine blade passing in front of the tower could generate extremely low frequency impulses. Van den Berg did not consider that this infrasound was audible, but there is no doubt that he fully acknowledged its presence.
This second paper was presented at the conference on Low Frequency Noise in Maastricht in August/September 2004. Dr H.G. Leventhall was one of the conference organisers, and subsequently edited the proceedings.
In 1989, NASA identified & reported that a windfarm in Hawaii, with modern-style upwind rotors, was generating impulsive infrasound & low frequency sound which they attributed to the effects of the rotor passing through wind-gradients and shadowing. They analysed the sound characteristics, and then simulated numerically how different wind-gradients could give rise to such effects.
I have myself analysed data from a windfarm in Michigan, which was generating unambiguous impulsive infrasound. It was possible to identify separate impulsive contributions from six different turbines at distances of 1500 feet to 1.2 miles. The maximum power spectral levels for the discrete frequencies associated with the harmonics of the impulses was 64dB SPL. But the overall rms sound power level was 77dB SPL, and the peak of the time waveforms of the impulses was 88-90dB. This indicates one of the major errors that has consistently been made in assessing infrasound from wind-turbines. Examining rms power spectrum peaks shows only 64dB, while comparing time domain impulsive peak levels shows 88-90dB. This represents ~25dB difference in the assessment of the infrasonic intensity.
I explicitly pointed out this feature at the Stratford Conference on Low-Frequency Noise in May 2012, and at the Internoise Conference in New York in August 2012. I would comment that I first became aware of the physical effects of infrasound when working extensively on site with an industrial gas turbine in 1980. I identified specific aspects which were closely related to some symptoms of sea-sickness with which I was very familiar, being a keen offshore sailor. Thus I did not doubt that infrasound under some circumstances can cause adverse effects, and the relationship to sea-sickness implied that there was probably some interaction with the balance mechanisms of the inner ear. So the more recent work of Dr Nina Pierpont did not strike me as heresy – rather, it endorsed an opinion that I had formed from my own direct, first-hand experience in an entirely different context, almost 30 years earlier.
Sincerely, Malcolm Swinbanks
(1) Infrasound from Wind Turbines – Fact, Fiction or Deception. Geoff Leventhall. Canadian Acoustics Vol 34 No 2 (2006) p 29
(2) Effects of the wind profile at night on wind turbine sound. G.P. van den Berg. Journal of Sound and Vibration Vol 277 (2004) p 955
(3) Do wind turbines produce significant low frequency sound levels? G.P. van den Berg. 11th International Meeting on Low Frequency Noise and Its Control, Maastricht, 30 August–1 September 2004
(4) Noise Radiation Characteristics of the Westinghouse WWG-0600 (600kW) Wind Turbine Generator. K.P. Shepherd, H.H. Hubbard, NASA TM101576 July 1989
The letter itself can be downloaded from http://www.wind-watch.org/documents/infrasound-from-wind-turbines-letter-from-malcolm-swinbanks/
Of critical concern to me is the evolution of Professor Leventhall’s court evidence and public statements on the importance of physiological stress resulting from exposure to low frequency noise. In his 2003 DEFRA document, section 10 dealt with the known associations between physiological stress and exposure to low frequency noise. One example given is of the research showing that sleeping children developed elevated cortisol (a stress hormone) following exposure to truck induced low frequency noise.
Court evidence given by Professor Leventhall in 2009 in a Suncor case is telling – it only refers to psychological effects from environmental noise, and there is no mention of the existence of a direct physiological effect, which clearly Professor Leventhall knew about in 2003, because he wrote about the physiological effects in section 10 of the DEFRA Literature Review. In that court evidence in 2009, Professor Leventhall stated:
“… Pierpont defined the symptoms of the Wind Turbine Syndrome as: ” … sleep disturbance, headache, tinnitus, ear pressure, dizziness, vertigo, nausea, visual blurring, tachycardia, irritability, problems with concentration and memory, and panic episodes associated with sensations of internal pulsation or quivering when awake or asleep.” “I am happy to accept these symptoms, as they have been known to me for many years as the symptoms of extreme psychological stress from environmental noise, particularly low frequency noise “ (emphasis added)
Whilst stress of either sort or in combination can have serious adverse health effects, particularly if it is chronic, the distinction is important. Omitting any reference to physiological stress appears deliberately misleading when the evidence about its existence in response to both infrasound and low frequency noise, in both animal and human studies, is clear. This denial by omission supports the deceptive notion that the “attitude” of the resident to the noise is the only consideration – change the “attitude” and the problems will go away. Problems are occurring in people such as wind turbine hosts and their families, and people working on the turbines, and people who cannot see the turbines, which is suggestive that the physiological changes are very important, rather than the emphasis currently placed on the psychological attitude of the sick person alone.
This emphasis of the psychological stress component without reference to the physiological stress issues also promotes a ‘victim blaming’ position towards those sick residents who don’t have the right “attitude” towards the noise, or who find that the proposed “cognitive behaviour therapies” suggested by Professor Leventhall do not work for them. I have had direct contact from a former participant in Professor Leventhall’s study of cognitive behaviour therapy in this context, and was told that despite intense effort, she did not find relief from the techniques offered, and so was dropped from the study. I wonder how many others this happened to?
Ignoring the evidence of a physiological stress response as a primary effect from infrasound and low frequency noise exposure creates the scientific void for the “nocebo” argument. This remains the sole argument used by those who are resistant to the growing evidence of a serious problem, and also used by those who would prefer concerned health professionals were silenced with false accusations of scaremongering “causing” the reported symptoms. I am not aware of research evidence for the nocebo effect in this circumstance, rather the evidence collected by Dr Bob Thorne and submitted to this inquiry suggests that health deteriorates with longer term exposure. That is certainly consistent with the reports from the residents, and consistent with what we know of the effects of chronic cumulative sleep deprivation and chronic cumulative stress.
Furthermore, the descriptions of symptoms I have been given by sick residents strongly suggest that the physiological stimulus response comes first, and that over time when there is no relief from the symptoms and the sleep deprivation, the psychological stress is magnified, further compounding their problems, just as Professor Leventhall pointed out in his DEFRA 2003 paper.
The study by the Chinese researchers in 2004 of physiological changes (blood pressure and heart rate) in response to infrasound stimuli for a short period of time, is clear evidence of a physiological response to infrasound in a laboratory study. The link to the original Chinese study is http://www.wind-watch.org/documents/an-investigation-on-the-physiological-and-psychological-effects-of-infrasound-on-persons/
Professor Leventhall goes on to mention the importance of understanding the correct exposure “dose” of precise frequencies, and I concur with him that this is essential. However he then asserts that the levels of infrasound from wind turbines are insufficient to cause the physiological effects being reported by the residents, but provides no research evidence of the measurements of the full acoustic spectrum inside homes, nor does he show the multidisciplinary research which would support his assertion. It has not yet been done, and urgently needs to be.
Concurrent full spectrum acoustic and vibration monitoring outside and within homes, as well as sleep studies, with physiological monitoring of EEG, ECG, blood pressure (perhaps via a less stimulatory method such as pulse transit time) and serial cortisol saliva samples would yield much useful data.
Acoustic field survey data is showing the presence of these frequencies below 200 Hz, at the time people are getting symptoms (eg Rob Rand & Stephen Ambrose, who unexpectedly became sick themselves with the characteristic range and pattern of symptoms whilst conducting an acoustic survey in Falmouth – see http://www.wind-watch.org/documents/bruce-mcpherson-infrasound-and-low-frequency-noise-study/ )
In reality, we have very little data about the actual acute and chronic exposures of infrasound, low frequency noise, and vibration, for individuals living and working inside these homes and workplaces. Residents living near wind turbines are describing symptoms and perceptions, which are suggestive that at different times the wind turbines could indeed be inducing symptoms and a physiological response which are causally related to sound and vibration energy, which they only experience when the wind turbines are turning and vary with wind direction and weather conditions.
Contrary to what Professor Leventhall asserts in paragraph 17, I can certainly distinguish between the resident’s reports of their perception of vibration, compared to their perception of audible noise or other sensations. The residents give very clear histories. The Shannon paper from the US Military was mentioned, because that experiment revealed that some of the chickens exposed to vibration as an embryo developed crossed beaks, and the same has been reported as a new phenomena by residents living near wind turbines who have chickens. When residents also report that they are perceiving vibration through the ground or through their beds, at which times they feel very unwell, and when there is evidence of seismic transmission of wind turbine acoustic energy, from Scotland, Germany and other locations, there is a need to measure ground vibrations, and expand the current knowledge base, rather than to continue to assert “there is no problem” or “there is no evidence of a problem”. The warning signs are there in both the existing acoustic and animal research and clinical evidence and adverse health reports from the residents that this could be a problem, as with the infrasound and low frequency noise from wind turbines. As Professor Warwick Anderson from the NHMRC pointed out in his oral evidence to the Federal Senate inquiry last year, an absence of evidence does not mean there is not a problem, and these sorts of anecdotal reports commonly form the basis upon which research is formulated, can provide helpful clues, and ring alarm bells.
Dr Malcolm Swinbanks, the British acoustic colleague of Professor Leventhall has stated he disagrees with Professor Leventhall’s assertion that the wind turbine sound energy is occurring at levels which are insufficient to cause these reported symptoms. Dr Swinbanks highlights another crucial issue – that historical acoustic measurement techniques have significantly understated the true peaks or “doses” – see repeat of the crucial part of the previously quoted letter below:
“The maximum power spectral levels for the discrete frequencies associated with the harmonics of the impulses was 64dB SPL. But the overall rms sound power level was 77dB SPL, and the peak of the time waveforms of the impulses was 88-90dB. This indicates one of the major errors that has consistently been made in assessing infrasound from wind-turbines. Examining rms power spectrum peaks shows only 64dB, while comparing time domain impulsive peak levels shows 88-90dB. This represents ~25dB difference in the assessment of the infrasonic intensity (my emphasis)
In other words, the peaks of infrasound from wind turbines have been significantly understated, thus underestimating the actual “dose” of infrasound and low frequency noise people would be receiving.
Professor Leventhall in a journal article in 1994 commented that levels of 60dB low frequency noise inside a home can cause neighbourhood noise nuisance problems for the residents, and that he was aware that other acoustics researchers such as Bryan had “suggested that it was the slopes and “turnover points” of the spectra of low frequency noises, rather than their absolute levels, which could be important in determining annoyance”. (from Leventhall, 1994, “Low Frequency Noise in ventilation systems – criteria and active control” in Journal of Low Frequency Noise and Active Control, pp 123 – 131)
Levels higher than 60dB are being measured at times by acousticians such as Rick James in the vicinity of homes where people are describing symptoms (personal communication with Rick James, 25/11/2012).
Dr Swinbanks kindly gave me permission to reproduce his email to me sent on 25th November, 2012, on this specific issue, in response to what Professor Leventhall had written in his response to this Senate inquiry, which is copied in full below:
Two comments. First, the 2004 Chinese paper that I have quoted in my recent Internoise 2012 publication described adverse physiological and psychological effects after an hour’s exposure to infrasound at 2.14Hz and 110dB. The threshold of hearing at 2.14Hz is typically ~ 120dB. So infrasound 10 decibels below the accepted threshold of hearing was reported as causing adverse effects in scientific laboratory tests which were subsequently reported in a peer-reviewed paper, published in the very same journal of which Dr Leventhall was an editor. (my emphasis)
This peer-reviewed paper negates his statements that infrasound can have no effect below the audible threshold. (my emphasis)
Secondly, modern upwind rotor wind turbine noise at extremely low frequencies can under certain circumstances be periodic and impulsive, as has been measured independently by several organisations. At the May 2012 Conference on Low Frequency Sound, organised by Dr Leventhall, I presented theoretical arguments as to the temporal shape of these impulses. My arguments were endorsed in the very next paper, by Richarz, who had quite independently derived exactly the same shape by the autocorrelation of actual measurements:
Can Infrasonic Lift Noise from Wind Turbine Rotors Contribute to Audible Sound? Werner Richarz, Echologics Engineering, 6295 Northam Dr. #1, Mississauga, ON, Canada, [email protected]
Dr Leventhall represents that low-frequency noise from wind-turbines is essentially random, without character. A central feature of periodic infrasonic impulses is that they are made up of a series of multiple tonal harmonics, all synchronised, and it has been well-known for 30 years that the peak sound pressure levels of periodic impulses can be as much as 20dB higher than the amplitude of the individual harmonics. Consequently, they can be very much more perceptible than the individual harmonics.
Malcolm Swinbanks, MA., PhD (Cambridge, UK)
The link to the paper presented by Dr Swinbanks at the New York Internoise conference in August 2012 is at http://www.wind-watch.org/documents/infrasound-from-wind-turbines-letter-from-malcolm-swinbanks/
The final paragraph in the above email from Dr Swinbanks leads to the next issue of contention, which is well outside of my area of expertise, so I have again sought the advice of Professor Leventhall’s peers. In paragraph 15 of his response to the Senate inquiry, Professor Leventhall states “Wind turbines produce a band of continuous low level noise” and goes on to say “The results of investigations of tonal noises cannot be transferred to wide band wind turbine noise. Dr Laurie is incorrect to do this”. There are number of Professor Leventhall’s acoustic peers who do not agree with his statement about wind turbines producing a band of continuous low level noise, based on their actual acoustic survey data which they tell me clearly shows the noise is in fact tonal, in the infrasound region particularly. Dr Swinbanks states that in the last paragraph above, and Steven Cooper has made that very clear to me in discussions with him about his full spectrum acoustic data from Australia.
Steven Cooper’s primary submission to this senate inquiry shows acoustic data collected from Australian wind developments in the appendices, where the narrow band spectra unequivocally identify tonal components and a periodic pattern / harmonics that occur in the infrasound region. By contrast, Professor Leventhall does not produce data of his own, just states that “wind turbines produce a band of continuous low level noise”, despite the mounting evidence from his peers to the contrary.
Therefore, it would appear that it is indeed valid to compare the clinical consequences and symptoms of exposure to other forms of low frequency noise with tonal components. Rick James, an acoustic colleague from the USA has written a very interesting and detailed paper exploring the history of low frequency noise problems, and highlights the links to work done by Professor Leventhall and others in helping to identify and solve the problems of “sick building syndrome”. The James paper is attached to this document.
With respect to Professor Leventhall’s assertions that the material in the NIEHS literature review is not relevant because the “doses” of infrasound energy are too high, I make the following remarks. Firstly, we don’t know what the current doses are, especially inside well insulated homes, with the exception of data collected already by James, Rand, Ambrose, Cooper and Thorne, which show that the levels are at times above the 60dB level which was identified as problematic for some neighbourhood noise nuisance cases in 1994 by Leventhall. Secondly, as Dr Swinbanks has pointed out, the current measurement practices appear to have markedly understated the actual exposures to infrasound. Thirdly, people are exposed chronically to wind turbine noise, and with the lack of data that exists on chronic exposure, the results from the animal studies with short term exposures at higher doses are very concerning, not reassuring, as there are a number of studies which show that chronic exposure to lower “doses” can still induce an effect which could be harmful, especially with prolonged exposure.
The 2001 NIEHS Literature review authors stated they were unable to obtain any data on sub chronic or chronic exposure to infrasound. (see http://www.wind-watch.org/documents/infrasound-brief-review-of-toxicological-literature/ ) So there is no animal data which recreates the circumstances and exposures of the human “guinea pigs” living in the neighbourhood of industrial wind turbines. Yet serious health problems are being reported, around the world, in the vicinity of these developments, by residents and by clinicians, which are consistent with the reported pathology in these animal experiments.
Page 24 of the literature review gives details of experiments with short term exposure to infrasound, with some disturbing results. They include the following:
Reference number 55:
(Alekseev, SV et al, 1985) Rats and guinea pigs (5 test animals, 2 controls per group) were exposed to infrasound (4 to 16 Hz) at 90 to 145 dB for 3 h/day for 45 days; and tissues were collected on days 5, 10, 15, 25, and 45 for pathomorphological examination. A single exposure to 4 to 10 Hz at 120 to 125 dB led to short-term arterial constriction and capillary dilatation in the myocardium. Prolonged exposure led to nuclear deformation, mitochondrial damage, and other pathologies. Effects were most marked after 10- to 15-Hz exposures at 135 to 145 dB. Regenerative changes were observed within 40 days after exposure.
The above report identifies that damage to heart muscle can occur from the effects of arterial constriction. Adrenaline surges can cause such constriction, and pathology related to such adrenaline surges has been reported (Tako Tsubo heart attacks, and Acute Hypertensive crises), but in the absence of the usual clinical precursors. There have been reports of young fit people developing characteristic symptoms of angina with prolonged exposure to wind turbines when living and working near wind turbines on their farms. The symptoms have gone away when they moved from their home. There are consistent reports of people with pre-existing cardiac disease finding their symptoms worsen with exposure to operating wind turbines, with their treating doctors urging them to leave their homes because of this. This animal data is therefore concerning, as it indicates that damage can occur in animals with only 3 hours of exposure, albeit at doses which may never be measured inside the homes of these residents. But what happens with longer exposures at lower doses? What is a safe dose? What are the actual doses at specific frequencies these people are being exposed to?
Reference number 58:
(Dadali et al, 1992) Prolonged exposure (up to 60 days) of rats to 8 Hz at 100 dB led to significant biochemical and morphological changes in the blood and tissues. Dosing the rats with even small doses of imidazoles (ethimizole and T-5) provided a marked protective effect, acting on the antioxidant status of the body. In the experiments, male rats of no specific strain (10/group) were exposed to 8 Hz at 100 dB for 3 h/day for 2 months with and without dosing with ethimizole or T-5, which were also tested alone. The authors reported variable effects of the imidazoles on infrasound-induced changes in erythrocyte concentrations of catalase, malonic acid dialdehyde, and glutathione reductase and the plasma concentrations of alanine aminotransferase, aspartate aminotransferase, and ceruloplamsin. Infrasound exposure induced tissue changes (destructive and atrophic changes of a focal character without marked gross disturbances in the lungs, liver, and kidneys as well as foci of proliferation of stromal elements) that were moderated by the imidazoles. Only insignificant peribronchial infiltration was noted after dosing. Dystrophic changes in the liver, heart, kidneys, adrenals, and testicles were lowered to a minimum.
This experiment is of significance, as it has been demonstrated that antioxidants reduced the damage in the intervention group, which suggests that oxidative stress is one of the pathways of damage. Of concern is that again, the exposures were of only 3 hours per day for 2 months, at 100dB. What about the residents who are exposed 24/7 for 25 years when the turbines are operating, at unknown doses of infrasound and low frequency noise, and reporting symptoms and exacerbations of worsening pre existing inflammatory conditions, which resolve when they are away from their homes? These animal experiments provide some important clues as to what might be occurring with prolonged exposure to wind turbine infrasound, at lower doses of sound energy.
There are also more recent reports of research from China, indicating that concerns about physiological stress and their neurobiological consequences are well founded in the animal experiments. I have attached the abstracts of three peer reviewed published research papers which are of relevance.
Finally, Professor Leventhall has stated in paragraph 8 of his response, that he has no conflict of interest. He does not appear to have declared the fact that he has given evidence on a number of occasions for wind developers in court matters in Ontario and in the USA, and is a coauthor of a document which is described as an “independent” review but was commissioned by the American and Canadian Wind Energy Associations, and was relied on extensively in the NHMRC Rapid Review. It also begs the question as to why Professor Leventhall requested that his involvement in the NHMRC Rapid Review as a peer reviewer be kept confidential.
This NHMRC 2010 Rapid Review has been, and still is, being used by wind developers, and government departments, to assert “there are no health problems”, and that “there is no evidence of any health problems”. It is still being used for this purpose in Australia and internationally.
The 2010 NHMRC Rapid Review is inadequate and misleading, particularly because of the omission of the Leventhall DEFRA 2003 Literature Review, which clearly stated that wind turbines were a source of infrasound and low frequency noise. Professor Leventhall was one of two peer reviewers of that document.
This also raises some questions for the NHMRC. What did the NHMRC ask Professor Leventhall about any conflict of interest issues. What was his response? Why this inadequate and compromised document (the 2010 NHMRC Rapid Review) not yet been withdrawn? Why has there been no specific call for targeted research into this problem, which the Federal Senate inquiry recommended 17 months ago? A repeat literature review is currently being conducted, but that is not conducting research.
Finally, perhaps it is timely to reflect on what is essentially a “natural experiment” being conducted on the human guinea pigs who live in the vicinity of industrial wind turbines. Currently the pleas for help from the sick and vulnerable residents are being ignored, almost universally, the world over by the governments who are imposing this technology, by way of legislation which enables the placement of wind turbines in locations where it is inevitable they will harm human health. As I referred to my in “list of symptoms” document, some of the pathology being reported by these residents and their treating doctors is life-threatening.
The human guinea pigs in this “natural experiment” have not given voluntary consent, relevant animal and human experiment results are being ignored, considerable physical and mental suffering is being reported and universally ignored by governments around the world, there is certainly a risk of death from cardiac disease, and suicide due to the severity of the mental health problems, the human subjects are not at liberty to bring the experiment to an end, and the wind industry and responsible authorities and elected representatives in the fields of health, noise regulation and planning show no signs of acting responsibly.
The international wind industry, and the acoustic consultants who work for it, have played an integral role in denying the existence and severity of the serious health problems. This behaviour has allowed this global industry to continue operating without an adequate precautionary approach being adopted by governments, to protect their citizens. It is time for the multidisciplinary research to occur, by truly independent researchers with no financial connection to the wind industry and who are not otherwise susceptible to its influence.
It is also time for greater transparency of the wind industry, by the provision of the wind mast data and ongoing real time acoustic monitoring, such as this Excessive Noise Bill proposes.
Dr Sarah Laurie CEO Waubra Foundation
Read Prof Leventhall’s letter to Dr Ian Holland to which this letter is a response