Health effects of wind turbines on humans in residential settings: Results of a scoping review.

Introduction: As the global number of wind turbines has increased steadily in recent years, as has the number of studies about putative health effects in residential settings, it is the review purpose to give an overview of the characteristics and methodologies of the scientific literature around the topic in order to identify research gaps and to derive implications for research and practice. Additionally, study findings from higher-quality observational studies as well as results that seem to be of interest for the scientific and political debate are presented.

Methods: The scoping review was conducted following systematic review methods. Comprehensive literature searches were carried out in several databases, and with extensive hand searches. All review steps were carried out in parallel by two reviewers or by one reviewer and in duplicate checked by another reviewer. The following important methodological criteria were investigated: Reporting, ethical aspects, generalization, selection bias, information bias, confounder bias. Findings from observational studies without a selection bias, information bias, and confounder bias are presented.

Results: 84 articles, that varied significantly in methods and outcomes assessed, met the inclusion criteria. Multiple cross-sectional studies reported that wind turbine noise is associated with noise annoyance, which is moderated by several variables such as noise sensitivity, attitude towards wind turbines, or economic benefit. Wind turbine noise is not associated with stress effects and biophysiological variables of sleep. Results on the impact of wind turbine noise on sleep disburbance, quality of life, and mental health problems differed among cross-sectional studies. There were few studies that addressed the potential impact of turbine noise on clinically apparent health outcomes. There were also few studies on visual risk factors or infrasound exposure. No literature was identified regarding low-frequency noise, electromagnetic radiation, and ice throw.

Conclusions: There is an extensive and diverse body of evidence around health impacts of wind turbines in residential settings, that increased sharply since 2010, showing particularly noise consequences concerning increased noise annoyance with its complex pathways; no relationship between wind turbine noise and stress effects and biophysiological variables of sleep; and heterogeneous findings concerning sleep disturbance, quality of life, as well as mental health problems. Research gaps concern the complex pathways of annoyance, the examination of clinically apparent health outcomes in comparison with non-exposed residents, an objective investigation of visual wind turbine features, the interaction between all wind turbine exposures, and epidemiological observational studies on field low-frequency and infrasound from wind turbines. Future research needs thorough high-quality and prospective study designs.