The Acoustical Society of America (ASA) is the largest acoustic society in the world, with a broad range of views readily available at major biannual conferences, with one of the most respected scientific journals in the world. The acoustic aspects of industrial wind turbine impacts on humans, and indeed options for mitigation of that noise, are major journal and conference discussion topics.
Unfortunately the CEO was unable to attend in person, however fortunately Professor Robert McMurtry, from Canada, made the presentation on her behalf:Download the Waubra Foundation Presentation,
made by Dr McMurtry on behalf of Sarah Laurie
The following Briefing Notes were prepared as Comments for Discussion, in advance of the conference, to be used as discussion points in determining the priority directions for further wind turbine noise and health research at the special research meeting convened after the conference session on Wind Turbine Noise. They have been made publicly available at the request of health, research, and acoustic colleagues working in this area.
The following comments would have been made in person had I been able to attend this meeting in Pittsburgh. I would be delighted to discuss them further with interested parties, and hope they are useful.
What We Already Know
- Infrasound and low frequency noise (ILFN) have a range of known, potentially serious, adverse health impacts, if the dose is excessive – physiological, tissue pathological (VAD), and psychological. Longterm exposure to excessive ILFN is causing immunosuppression, resulting predictably in chronic infections and cancers, as well as potentially fatal cardiovascular diseases, known to be associated with chronic sleep deprivation and chronic stress.
- People do not habituate to the ILFN sound energy – rather they become progressively sensitized to it. Steven Cooper’s recent detailed data collection is the most comprehensive – but comprised only six subjects, however his results were consistent in that people chronically sensitized for 6 years report perceiving sensations (from ILFN) at around 50 dB (rms) with what appears to be a peak sensitivity at around 4–5 Hz (narrow band analysis)
- Amplification inside homes can occur, so measurements outside homes will not accurately represent the true exposure doses inside homes, especially at the lower sound frequencies in the infrasound range (0 – 20 Hz)
- From a public health perspective, we need noise pollution guidelines which protect sleep and which do not induce repeated physiological stress responses (annoyance) – we know that both sleep deprivation and chronic stress have serious long term health consequences
- Wind turbine noise with its capacity to produce heightened noise zones with the transient pulse pressure peaks appears to be inducing serious adrenaline surge pathology – and there is no way of preventing these occurrences other than restricting siting and operation of multiple turbines. Where these heightened noise zones are occurring inside people’s homes when they are trying to sleep, the consequences especially from the larger wind turbines where there are large numbers of them, are severe, as reported by multiple residents (eg Macarthur wind development with 140 x VESTAS V 112 3 MW turbines in Victoria, Australia)
- Vibration is another possible area of risk – especially to developing embryos if exposed at a critical time in their development can result in fetal deformities. Fetal deformities, increased stillbirths, and miscarriages have already been reported by a vet in Denmark with respect to a mink farm. It is therefore possible in humans as well as animals – we just don’t yet know the threshold dose or the current exposure doses. There may well also be a synergistic effect with airborne pressure pulsation effects from ILFN.
What is now required, urgently
- Full spectrum acoustic testing – inside and outside homes, (including vibration as well) for sufficient duration (weeks) to cover a range of weather conditions, wind directions, and operation of the wind turbines including worst case scenario as reported by the residents, and needs to include “on off” testing, full provision of relevant data, and full cooperation of the operator. Governments must insist on this, especially if subsidies are being paid.
- Concurrent physiological testing inside homes first including EEG, heart rate, non invasive blood pressure measurement (eg pulse transit time) and biomarkers for stress, including sequential salivary cortisol, neuro peptide Y, and some of the new markers for genetic damage from short term sleep deprivation could also be used (Emeritus Professor Alun Evans from Ireland, is a useful source of information about this recent research).
- Carefully supervised laboratory research could then follow if and when absolutely necessary, bearing in mind that there are potential risks of injury and fatalities using infrasound generators in laboratories, so extreme care must be exercised whilst using this equipment.
- Dr Bob Thorne’s health indicator data collection from his study at two Victorian Wind Developments provides a useful collection of standardized questionnaires which have international and national norms for comparison. These could be utilized internationally.
Who to test / investigate?
It is my strong view that those who report the most serious symptoms and those with the longest chronic exposures who report symptoms and sensations, must be the priority to investigate, to determine exposure doses at which they are demonstrating a physiological response. The priority must be to investigate the sleep disturbance first, because of the overwhelming importance of sleep for the maintenance of good physical and mental health. Children should not be excluded from observation of the impacts on them – indeed they are a priority to protect, especially children with special needs including neurodevelopmental issues, and conditions such as epilepsy where sleep disturbance could significantly increase the risk of seizures. Wind turbine host families should be offered the opportunity to be involved in such research, and nondisclosure clauses in any agreements with developers must be declared null and void so they can participate in such research.
In my view it is not a priority to investigate people who do not report an adverse impact. That will not tell us anything new and is a waste of precious resources – we already know that some people are not affected at doses where others are severely adversely impacted, because this is reported by families all the time, and we already have some clues as to who is susceptible, thanks to Dr Pierpont’s research and the research of others including Dallos (size of the helicotrema plays a part in sensitivity to LFN). So too does certain medication – eg narcotic analgesia also appears to increase sensitivity to ILFN. Nussbaum also established individual variation in 1985.
Objectives of the research
- Establish direct causation of sleep disturbance and specific symptoms and sensations, often referred to as “annoyance” symptoms by engineers / acousticians with expertise in low frequency noise problems. In other words, establish which frequencies, and which “doses” of sound energy are inducing the symptoms/sensations, particularly the sleep disturbance
- Establish thresholds of perception including where sleep disturbance is triggered in chronically sensitized people. Their exposure dose (both measured acutely, and calculated with respect to the months/years of exposure) must be established.
- Establish the exposure doses of people when they are reporting severe acute impacts both inside and outside – development of a portable dosimeter device is a priority especially for those who have already had an adrenaline surge episode of either an acute hypertensive crisis or a Tako tsubo event or who are experiencing pressure bolt sensations.
There are reports of adverse impacts thought to be from excessive ILFN at the following in Australia, for example:
- Residential homes
- Aged care facilities
In the case of jails there is the international convention against Torture to consider – jail inmates cannot escape the adverse impacts by removing themselves, and I suspect Australia is not alone in allowing the siting of ILFN emitting industrial developments not far from jails. Jail cells make perfect infrasound resonators, (Kelley 1982 comments about the impacts being worse in small rooms).
Noise sources other than wind turbines:
Wind turbines are not the only sources of excessive impulsive ILFN. In Australia other locations include gas fired power stations, coal fired power stations, underground coal mine extractor fans, open cut coal mines – diesel machinery. It would be preferable to ensure that the adverse health impacts from different noise sources are investigated – the above adverse health effects are of course not confined to wind turbines.
Finally, numerous international human rights conventions and covenants generally include the proviso that member states should ensure their citizens can attain the best possible mental and physical health. It is not possible to comply with the provisions of these UN Conventions and Covenants unless noise pollution (including from infrasound and low frequency noise and vibration) is regulated so that the regulations are effective to protect health, and in particular sleep.
I hope these comments are helpful, and look forward to helping progress the research agenda by sharing the Waubra Foundation’s knowledge of the impacts and the relevant research.
CEO, Waubra Foundation
Bachelor Medicine, Bachelor Surgery, 1995 Flinders University
Former Rural General Practitioner
Former Fellow and Examiner, Royal Australian College of General Practice
Former Fellow of Australian Rural College of Remote and Rural Medicine
Former Member of South Australian Branch Council of the Australian Medical Association