Scientific Journal Publications

1. Michaud et al. (2013, December). Self-reported and Objectively Measured Health Indicators among a Sample of Canadians Living within the Vicinity of Industrial Wind Turbines: Social Survey and Sound Level Modelling Methodology. Noise News International, 21(4): 14-23.

Health Canada provides advice on the potential health impacts of environmental noise, including that from wind turbines. In collaboration with Statistics Canada, Health Canada is conducting a multi-year research study to explore the relationship between wind turbine noise and possible health effects on individuals living near wind turbines. Wind turbine noise levels at dwellings selected for the study are modelled according to International standards and supported with specialised sound level measurements inside and outside a subsample of homes. An in-person computer based questionnaire evaluates participants' perception of community noise, general health, and sleep quality. In addition, the study includes objective measurements for blood pressure, stress and sleep. The overall research design for the study is complex and includes many different variables. For this reason, and in order to provide a baseline reference in support of future publication of results, Health Canada has published the study's elaborated methodology in the journal Noise News International (Dec 2013). The results of this research will strengthen the peer-reviewed scientific evidence base and, when considered together with other science in this area, support decisions, advice and policies regarding wind turbine development proposals, installations and operations in Canada.

2. Feder et al. (2015). An assessment of quality of life using the WHOQOL-BREF among participants living in the vicinity of wind turbines. Environmental Research, 142 (2015): 227-238.

There is concern among some Canadians that living within the vicinity of wind turbines may have adverse health implications. The Wind Turbine Noise & Health Study (WTNHS) was conducted by Health Canada, in collaboration with Statistics Canada and other external experts, to understand the effects of wind turbine noise (WTN) on health and well-being. Researchers used internationally accepted methods to calculate WTN levels at participants' dwellings. Health effects in the WTNHS were assessed by asking participants to respond to questions about their health, including questions related to their quality of life (QOL). The World Health Organization (WHO) developed an abbreviated version of their 100-item QOL questionnaire reducing the length to 26 questions. The shorter version is referred to as the WHOQOL-BREF and has been used in several QOL studies for many years. The WHOQOL-BREF provides an assessment of QOL in the following areas: Physical health, Psychological, Social relationships and Environment. In addition, there are two questions that evaluate overall QOL and Satisfaction with Health. The results of the WTNHS suggested that QOL was not influenced by exposure to WTN. This means that in the WTNHS the pattern of responses on the WHOQOL-BREF questionnaire did not depend on the level of WTN at the participants' dwelling. These results, when considered together with other findings in this area, strengthen the advice that Health Canada provides on the health effects of WTN exposure.

3. Michaud et al. (2016, January). Effects of Wind Turbine Noise on Self-Reported and Objective Measures of Sleep. SLEEP, 39(1): 97-109.

There is concern among some Canadians that living within the vicinity of wind turbines may have adverse health implications. The Wind Turbine Noise & Health Study (WTNHS) was conducted by Health Canada, in collaboration with Statistics Canada and other external experts, to understand the effects of wind turbine noise (WTN) on health and well-being. Health effects in the WTNHS were assessed by asking participants to respond to questions about their health, including questions related to their sleep. The Pittsburgh Sleep Quality Index (PSQI) is a validated questionnaire evaluating sleep quality over the previous 30 days, and was included as part of the questionnaire administered in the WTNHS. In addition to the questionnaire, a subsample of almost 700 participants in the WTNHS also wore a sleep watch for up to 7 days. The sleep watch was used to record movements providing an objective indication of different sleep parameters which included how often people awakened, how long they slept and how long it took to fall asleep. Measures of sleep were assessed in relation to calculated WTN levels at participant's households. The results of the WTNHS suggested that sleep was not influenced by exposure to WTN. Specifically, the responses to the sleep questions on the questionnaire and the data collected with the sleep watch were not found to be dependent on the level of WTN at the participant's household.These results, when considered together with other findings in this area, strengthen the advice that Health Canada provides on the health effects of WTN exposure.

4. Michaud et al. (2016, March). Self-reported and measured stress responses associated with exposure to wind turbine noise. Journal of the Acoustical Society of America, 139(3): 1467-1479.

There is concern among some Canadians that living within the vicinity of wind turbines may have adverse health implications. The Wind Turbine Noise & Health Study (WTNHS) was conducted by Health Canada, in collaboration with Statistics Canada and other external experts, to understand the effects of wind turbine noise (WTN) on health and well-being. Multiple measures of stress reported by, and objectively measured in, participants exposed to WTN were assessed in the WTNHS. The Perceived Stress Scale (PSS) is a widely used questionnaire designed to measure an individual's perception of stress during the previous month. Scores on the PSS were considered together with objectively measured blood pressure, heart rate and hair cortisol concentrations. Cortisol is a well-accepted stress hormone that increases with increasing stress. When the body releases cortisol in response to stress some of it will accumulate in hair and remain there as the hair grows. Because hair tends to grow at a rate of approximately 1cm every 30 days, the analysis of a 3 cm segment of hair collected in the WTNHS provided an estimate of cortisol production over the previous 90 days. Although this method has been used in several studies to assess long-term stress, the WTNHS represents the largest study in this area and the first to include this objective measure of stress in response to WTN. The results of the WTNHS showed that in the final models scores on the PSS, measures of blood pressure, heart rate and cortisol were all unrelated to WTN levels. These results, when considered together with other findings in this area, strengthen the advice that Health Canada provides on the health effects of WTN exposure.

5. Michaud et al. (2016, March). Exposure to wind turbine noise: Perceptual responses and reported health effects. Journal of the Acoustical Society of America, 139(3): 1443-1454.

There is concern among some Canadians that living within the vicinity of wind turbines may have adverse health implications. The Wind Turbine Noise & Health Study (WTNHS) was conducted by Health Canada, in collaboration with Statistics Canada and other external experts, to understand the effects of wind turbine noise (WTN) on health and well-being. This paper provides a description of several self-reported measures of health and well-being in relation to WTN levels. A total of 1238 adults between the ages of 18-79 years participated in the study from areas in southern Ontario and Prince Edward Island (PEI). This paper shows that self-reported health effects, which included, but were not limited to, migraines, dizziness, tinnitus, sleep disorders, perceived stress levels, chronic pain and heart disease were all unrelated to WTN levels. This means that there was no pattern between reporting these health effects and where people lived in relation to wind turbines. However, people that lived in areas with higher WTN levels were more likely to be highly annoyed by several wind turbine features, including noise, shadow flicker, visual impacts, vibrations and the blinking lights on top of turbines that serve as aircraft warning signals. These results, when considered together with other findings in this area, strengthen the advice that Health Canada provides on the health effects of WTN exposure.

6. Michaud et al. (2016, March). Personal and situational variables associated with wind turbine noise annoyance. Journal of the Acoustical Society of America, 139(3): 1455-1466.

There is concern among some Canadians that living within the vicinity of wind turbines may have adverse health implications. The Wind Turbine Noise & Health Study (WTNHS) was conducted by Health Canada, in collaboration with Statistics Canada and other external experts, to understand the effects of wind turbine noise (WTN) on health and well-being, which includes community annoyance. Annoyance in this context refers to a subjective belief that for a long period of time (approximately 1year) WTN is considered to be very or extremely annoying. Scientists consider responses of this nature to reflect a state of "long term high annoyance". Long-term high annoyance is considered to be more serious than a brief annoyance which may briefly disturb an activity. This paper presents multiple models as a way of identifying factors that predict WTN annoyance. The results show that although WTN levels on their own do predict annoyance, the strength of this prediction is substantially increased when other variables are included in the prediction models. These variables include, but are not limited to, other sources of annoyance (i.e., visual, blinking lights, vibrations), reported sleep disturbance, sensitivity to noise and receiving personal benefits from having wind turbines in the area. It was also found that reporting to be concerned about one's physical safety associated with having wind turbines in the area was a predictor of WTN annoyance. This paper also compares the findings from the WTNHS to similar peer-reviewed studies published by other researchers in this area and those related to other transportation noise exposures. The comparison suggests that the community tolerance toward WTN is lower when compared to aircraft, rail and road traffic noise. This means that, at comparable sound levels, annoyance to WTN is greater than it is toward these other noise sources. The current paper provides a quantification of these differences. These results, when considered together with other findings in this area, strengthen the advice that Health Canada provides on the health effects of WTN exposure.

7. Voicescu et al. (March, 2016). Estimating annoyance to calculated wind turbine shadow flicker is improved when variables associated with wind turbine noise exposure are considered. Journal of the Acoustical Society of America, 139(3): 1480-1492

There is concern among some Canadians that living within the vicinity of wind turbines may have adverse health implications. The Wind Turbine Noise & Health Study (WTNHS) was conducted by Health Canada, in collaboration with Statistics Canada and other external experts, in order to understand the effects of wind turbine noise (WTN) on health and well-being. Although the primary objective of this study was to characterize the community response to WTN exposure, the results showed an increase in annoyance towards other features, including shadow flicker with increasing WTN levels. Shadow flicker is caused by the sun's movement behind the rotating blades of the turbine and is known to cause complaints among some communities situated near wind turbines. Health Canada scientists calculated the duration of shadow exposure at households in the WTNHS using WindPRO™ software to develop predictive models. The results show a significant increase in annoyance when shadow flicker exposure was equal to, or greater than 20 minutes per day. In addition, it was found that some of the variables that were found to predict WTN annoyance were also significant predictors of shadow flicker annoyance. These included, but were not limited to, sensitivity to noise, concern for physical safety, being able to hear wind turbines from one's property, and other annoyances with wind turbine features (e.g. noise, blinking lights, visual, and vibrations). This paper concludes that although annoyance to wind turbine shadow flicker can be predicted by using only calculated WTN levels, there is a slight improvement in the strength of this prediction when calculated shadow flicker exposure models are used instead of WTN levels. This is further improved when other factors are considered. These results, when considered together with other findings in this area, strengthen the advice that Health Canada provides on the health effects of WTN exposure.

8. Keith et al. (2016, March). Wind turbine sound power measurements. Journal of the Acoustical Society of America, 139(3): 1431-1435.

There is concern among some Canadians that living within the vicinity of wind turbines may have negative impacts on health. The Wind Turbine Noise & Health Study (WTNHS) was conducted by Health Canada, in collaboration with Statistics Canada and other external experts, in order to understand the effects of wind turbine noise (WTN) on health and well-being. This paper provides experimental validation of the sound power level data provided by the wind turbine manufacturers for use in the WTNHS. Using international standards, sound power levels were measured from the 10 wind turbine models present in the WTNHS area. Measurements were consistent with the data provided by manufacturers. The measurements also allowed the manufacturers' data to be extended to lower frequencies. Including these low frequencies, the resulting frequency spectra were similar for all 10 turbine models; thereby making it more difficult to determine if there are any unique effects from low frequency noise. Published findings are consistent with previously released findings outlined on the Health Canada website.

9. Keith et al. (2016, March). Wind turbine sound pressure level calculations at dwellings. Journal of the Acoustical Society of America, 139(3): 1436-1442.

There is concern among some Canadians that living within the vicinity of wind turbines may have negative impacts on health. The Wind Turbine Noise & Health Study (WTNHS) was conducted by Health Canada, in collaboration with Statistics Canada and other external experts, in order to understand the effects of wind turbine noise on health and well-being. This paper describes the calculation of the sound pressure levels (SPL) from wind turbines at the homes of the 1238 survey participants in the WTNHS. Based on data provided by manufacturers, SPL was calculated outside of each home using internationally recognized standards. The SPL was manipulated using a method called C-weighting to emphasize the low frequency noise. For consistency, with the evaluation of most other noise sources, a method referred to as A-weighting was also used. Using C-weighting the SPL was consistently 15 dB higher than when using A-weighting, this difference confirmed that wind turbines produce low frequency noise. However, the simple consistent difference between A- and C- weighted SPL meant that neither weighting could provide any more information than the other. Typically, when siting wind turbines in Canada, the calculated SPL at dwellings assumes the wind speed is always constant. The same approach was used in the WTNHS. The wind speed chosen for analysis was 8 m/s, because this wind speed was associated with some of the highest sound levels from the wind turbines. In reality the wind does not blow continuously, so a realistic long term average SPL at the dwellings was calculated to be 4.5 dB lower than the SPL for constant wind speed. Ambient SPL was also estimated using guidance from the United States and Alberta, Canada. Published findings are consistent with previously released findings outlined on the Health Canada website.

10. Michaud et al. (2018, February). Clarifications on the Design and Interpretation of Conclusions from Health Canada’s Study on Wind Turbine Noise and Health. Acoustics Australia, https://doi.org/10.1007/s40857-017-0125-4

The Wind Turbine Noise & Health Study (WTNHS) was conducted by Health Canada, in collaboration with Statistics Canada and other external experts, in order to understand the effects of wind turbine noise on health and well-being.  It has been extensively communicated that Health Canada’s WTNHS did not find positive associations between wind turbine noise (WTN) levels and any of the evaluated health outcomes, beyond an increase in annoyance toward several wind turbine features (i.e., noise, shadow flicker, blinking lights, visual impacts and vibrations). Following the publication of the CNHS findings, there has been interest among some individuals to present alternative interpretations of the results of the WTNHS. While recognizing the importance of independent scientific re-evaluation and/or reinterpretation, this publication serves to clarify and, where necessary, correct some of the information put forward by others. This paper identifies substantial issues associated with the re-evaluation put forth. To thoroughly address these issues and to avoid further confusion or misinterpretation, the authors of the WTNHS provide a comparison between the WTNHS health condition prevalence data and nationally representative health-based surveys conducted in Canada during the same calendar year. In addition, this paper responds to comments received to date on the WTNHS, including the study’s age range, the generalization of findings, the provision of raw data, and conclusions on the association between WTN level and health.

11. Michaud et al. (2018, April). Derivation and application of a composite annoyance reaction construct based on multiple wind turbine features. Canadian Journal of Public Health, 109(2):242-251.

The Wind Turbine Noise & Health Study (WTNHS) was conducted by Health Canada, in collaboration with Statistics Canada and other external experts, in order to understand the effects of wind turbine noise on health and well-being. Noise emissions from wind turbines are one of multiple wind turbine features capable of generating annoyance. On social surveys, annoyance response options include “not at all”, “slightly”, “moderately”, “very”, and “extremely”. Most studies in community noise, including wind turbine studies, focus on the top two response categories and communicate this as “high annoyance” and they are typically limited to noise. No analysis to date can simultaneously reflect the change in all magnitudes of annoyance toward multiple wind turbine features. The primary objective in this study was to provide a single construct for overall annoyance to wind turbines based on reactions to noise, blinking lights, shadow flicker, visual impacts, and vibrations. The authors refer to this as an “aggregate annoyance” response and show how it changes as a function of exposure to wind turbines.  This is a novel approach to how community annoyance toward complex structures, such as wind turbines, can be communicated. The authors discuss how it provides a more complete assessment when compared to one limited to “high annoyance” toward only a single wind turbine feature, like noise.

12. Michaud et al. (2018, April). The association between self-reported and objective measures of health and aggregate annoyance scores toward wind turbine installations. Canadian Journal of Public Health, 109(2):252-260.

The Wind Turbine Noise & Health Study (WTNHS) was conducted by Health Canada, in collaboration with Statistics Canada and other external experts, in order to understand the effects of wind turbine noise on health and well-being. The authors of the current paper recently published a novel approach to how annoyance toward wind turbines can be communicated as an aggregated annoyance. Aggregate annoyance is a response that simultaneously accounts for all magnitudes of annoyance (i.e., “not at all”, “slightly”, “moderately”, “very”, and “extremely”) toward multiple wind turbine features (i.e. noise, shadow flickers, blinking lights, visual impacts and vibrations). The possible range in an individual’s aggregate annoyance score in the WTNHS was 0 (i.e., not at all annoyed by any of the 5 wind turbine features) to 20 (extremely annoyed by all 5 features). In the current paper, the authors show the average aggregate annoyance score for participants who indicated they had a health condition assessed in the WTNHS ranged from 2.53 to 3.72; the mean score for those who did not report health conditions ranged between 0.96 and 1.41. Household complaints about wind turbine noise had the highest average aggregate annoyance (8.02), compared to an average of 1.39 among those who did not complain. The setbacks associated with 1) where aggregate annoyance begins to significantly change and 2) when the aggregate annoyance scores reach levels associated with health symptoms/risk factors could be considered by jurisdictions responsible for decisions regarding wind turbine developments.

Conference Proceedings

Conference proceedings are a collection of technical papers presented at a professional meeting that are not subject to peer review by the publishing organization. In the interest of openness and transparency, copies of the following conference proceedings and/or abstracts are available upon written request:

• INCE Europe: Wind Turbine Noise 2015, Glasgow, Scotland
• 169^th meeting of the Acoustical Society of America, Pennsylvania, USA
• Internoise 2015, San Francisco, USA
• 171^st meeting of the Acoustical Society of America, Salt Lake City, Utah, USA

To obtain an electronic copy of the preceding documents, please send an email request specifying the document title to: ccrpb-pcrpcc@hc-sc.gc.ca.