Symptoms intuitively associated with wind turbine infrasound.

In many countries, a certain proportion of individuals living in the vicinity of wind power areas have reported symptoms that they have intuitively associated with infrasound from wind turbines. While the reason for these symptoms remains under debate, this is the first study to describe the phenomenon by assessing the prevalence and severity of these wind turbine infrasound related symptoms as well as factors associated with being symptomatic. Four wind power areas in Finland assessed to have the most problems intuitively associated with wind turbine infrasound were selected for the study. The questionnaire was mailed to 4847 adults in four distance zones (≤ 2.5 km, > 2.5-5 km, > 5-10 km, > 10-20 km from the closest wind turbine), and 28% responded. In the closest distance zone, 15% of respondents reported having symptoms that they have intuitively associated with wind turbine infrasound. In the whole study area, the symptom prevalence was 5%. Many of the symptomatic respondents were annoyed by audible wind turbine sound and associated their symptoms also with vibration or electromagnetic field from wind turbines. One third of the symptomatic respondents rated their symptoms severe, and the symptom spectrum was very broad covering several organ systems. In multivariate models, many factors such as proximity to wind turbines, impaired health status, being annoyed by different aspects of wind turbines and considering wind turbines as a health risk were associated with having wind turbine infrasound related symptoms. Although causal relationships cannot be assessed based on a cross-sectional questionnaire study, it can be speculated that interpretations of symptoms are affected by many other factors in addition to actual exposure.