LAUSR

The issue of wind turbine noise has raised concern in communities around the planet, from the Australian bush to Cape Cod, Massachusetts. Over the past decade, claims that wind turbine noise is harmful have proliferated in response to new and proposed wind energy projects, leading in some cases to significant public opposition, withdrawn projects, and even decommissioned turbines. Two reports in Environmental Health Perspectives (EHP) examine separate end points related to exposures to wind turbine noise. In the first paper, people over age 65 exposed to high levels of wind turbine noise at home appeared more likely to fill prescriptions for sleep medication. To a lesser degree, these individuals also appearedmore likely to fill prescriptions for antidepressants. The second EHP article assessed the risk of stroke and heart attack. The authors estimated a slight increase in risk of heart attack among those exposed to the highest noise levels, compared with the least-exposed group. Their results did not support an association with stroke. Four earlier papers produced by the same Danish governmentfunded research group, published throughout 2018, investigated associations between wind turbine noise and hypertension, cardiovascular events (in relation to short-term exposure), diabetes, and birth outcomes. None of those papers supported associations with wind turbine noise. To conduct their analyses, the researchers used national registries containing decades of residence and health data for hundreds of thousands of residents of Denmark. They also drew from federal data on more than 7,000 wind turbines in the country. The researchers stress that their results should not be interpreted as full exoneration of wind turbine noise. One reason is that the study population shrank substantially when limited to those whose homes were near enough to wind turbines to experience high levels of noise. This limit reduces statistical power and thus reliability when drawing conclusions about health outcomes associated with exposure to the loudest wind turbine noise, says lead author Aslak Harbo Poulsen, an epidemiologist with the Danish Cancer Society Research Center. “The cohort is quite huge, but only a very small proportion of these people have exposure levels that we would expect to potentially have an effect. We didn’t really know when we started out