February 18, 2018
Chicago and suburban residents under the O’Hare flight paths currently experience jet noise in the range of 65 - 110 decibels on a 24/7 basis. Those living immediately adjacent to the boundary of O’Hare, like the residents of Park Ridge, Bensenville, and the 41st Ward, experience noise levels close to 120 decibels (the sound at which aircraft take off).
A landmark study in Environmental Noise and the Cardiovascular System was published last week in the Journal of the American College of Cardiology (2018, 71: 688-697) by a group of German researchers at the University Medical Center Mainz Center of Cardiology. The study was covered by both international and US major media outlets but was mysteriously ignored by the local Chicago media. Considering that hundreds of thousands of people have experienced intolerable noise conditions over the last 4 years, it is bizarre that not one Chicago television, radio, or newspaper outlet covered its public health significance. Coverage of issues in the public’s interest are what defines accessible, relevant, and responsible journalism.
As the authors’ note, the question is no longer whether jet noise causes cardiovascular change in affected residents, it is the magnitude of the damage and the threshold of noise that leads to health risk. The authors reviewed environmental noise-exposure research and epidemiological studies over the last twenty years. Their review focused on the mechanisms and epidemiology of noise-induced cardiovascular disease and provided new insight into the process that underlie noise-induces vascular change. Currently, the behavioral experience of Chicago and suburban residents living under the O’Hare flight paths leads to general annoyance, stress, sleep disturbance, and impaired cognitive performance. The big question remains however. Does extreme jet noise exposure have a direct causal biological impact on residents?
According to the authors, noise annoyance and chronic stress, activation of the autonomic nervous system and the endocrine system, and sleep disturbance ultimately lead to blood vessel alterations in the short and long term contributing to cardiovascular disease. More specifically, chronic stress associated with repetitive adverse jet noise exposure generates increased blood pressure, changes in blood glucose levels, blood viscosity, blood lipid formation, and the activation of blood coagulation. Further, the review focused on heightened activation as a result of nighttime aircraft noise with excessive stress hormone (cortisol) release. Ultimately, these biological stress reactions inflame and damage the walls of blood vessels. And the authors note, the characteristic of noise such as pattern, frequency, exposure time, and intensity (characteristics currently found in abnormally high levels with aircraft arrival and departures from O’Hare), enhance the destructive impact on cardiovascular health.
In terms of sound threshold, the authors’ note an important relationship between increasing jet noise and health risk. They found a 6% significant increase in cardiovascular risk for every 10 decibel increase in aircraft noise. Further, aircraft noise above 55 decibels significantly increased risk for stroke hospitalization. Finally, the authors note that aircraft noise significantly increases risk for heart failure, ranging from 2% to 7% increase in risk per 10 decibel rise.
Regardless of what we are being told by our elected representatives about the negligible health and safety impacts of the O’Hare Modernization Plan, it is clear that realty is quite different. The evidence outlined here further strengthens the concept that O’Hare noise contributes to the development of cardiovascular risk of coronary artery disease, arterial hypertension, stroke, and heart failure.