The Vermont Health Department and the Vermont Department of Public Service persist in reassuring us that there are no significant health effects related to industrial wind turbines under Vermont’s current noise standards.
Such a blanket statement is not only incorrect, it is a disservice to the Vermonters who are already experiencing adverse health effects, such as headaches, vertigo, nausea, anxiety, ringing in the ears and, most importantly, chronic repetitive sleep disruption. There is an ongoing academic debate about the mechanisms behind these effects (direct vs. indirect, the nocebo “its all in your head” effect, audible vs. inaudible infrasound), but little disagreement that some persons living too close to these large wind turbines are suffering, whatever the mechanism.
Critical methodological shortcomings plague many of the large-scale industry or government-sponsored studies that state agencies rely upon to establish protective sound levels:
— Failure to measure the full sound spectrum, in particular ignoring the very low frequencies that are likely responsible for many of the reported adverse health effects.
— They assume a constant sound pressure and tone, not at all like the impulsive sound produced by large turbines, which has its own distinct signature that differs from other environmental sources (planes, trains, automobiles, wind, leaves rustling).
— Sound levels are often averaged over an hour, or longer, making it possible for periods of very loud intrusive sound to fall within an “acceptable” calculated level.
— Measurements are usually not taken indoors, where the sound may be more intrusive due to the well-established resonance effects of low frequency sound.
— Most importantly, the large studies fail to focus their investigations on those households that are most severely affected.
In spite of these research design limitations, a recently released large Health Canada study found that at wind turbine sound pressure levels greater than 35 dB(A), health-related complaints will increase, and at levels greater than 40 dB(A) a significant number of persons will be “highly annoyed” (meaning adverse health effects, especially sleep disturbance).
The current Public Service Board threshold of 45 dB(A) of audible sound through an open window, averaged over an hour, has actually never been proven safe or protective. Some studies recommend that audible sound should not exceed 35 dB(A), or 5 dB(A) above normal background sound levels. (This is crucial in rural areas where background noise is minimal, particularly at night). The level should be a maximum, not an hourly average. Above 35 dB(A) there are likely to be significantly more complaints, particularly difficulty sleeping.
Several recent small, well-designed, independent clinical studies ( Ambrose&Rand, Nissenbaum, Pierpont, Shomer, Cooper, Thorne) that do take the aforementioned factors into consideration, all conclude that lower, more protective noise limits for these huge industrial wind installations are needed.
To the benefit of the wind industry, and apparently to those agencies promoting large wind installations on our ridgelines here in Vermont, the issue of infrasound has thus far been successfully suppressed and ignored. Space does not permit a detailed discussion, but consider the following:
— The World Health Organization has definitively established (2009) that inaudible very-low-frequency infrasound is a human health hazard, that it can disturb sleep, and increase heart rate and blood pressure, leading in susceptible individuals, to permanent effects such as hypertension and cardiovascular disease, even at sound levels below 30 dB(A).
— In the mid 1980s, Neil Kelley and his team thoroughly documented significant adverse health effects resulting from inaudible, very-low-frequency sound produced by a large wind turbine in Boone, N.C. This scientifically rigorous NASA and Department of Energy-sponsored study, in cooperation with MIT and four other prestigious universities, as well as the wind industry, has been conveniently dismissed as irrelevant by current wind developers, even though the study’s conclusions have never been disputed, and even though we now know that the large turbines being installed today do indeed generate clinically significant amounts of infrasound.
— Three more recent preliminary studies ( Ambrose&Rand’s Falmouth, Mass., 2011; Shomer, Rand, et. al., Shirley project, Brown County, Wisconsin, 2012; Cooper, Bridgewater, Australia, 2014 ) of projects with large modern upwind turbines have replicated and confirmed Kelley’s findings; i.e., infrasound, not audible sound, is a major contributor to the health fallout from today’s industrial wind projects.
Taken together with the thousands of case reports from around the world (I personally have seen three families here in the Northeast Kingdom that have been forced to abandon their homes due to adverse health effects from nearby wind turbines), stricter full-spectrum noise standards for these large wind projects are urgently needed. However, Vermonters should not expect meaningful change until the governor, as well as his appointees in the Health and Public Service departments, recognize the importance of being more inclusive in their selection of scientific data, and until they demonstrate a genuine willingness to take the health complaints of the neighbors of these turbines seriously.
Dr. Sandy Reider is a physician who lives in Lyndonville