When discussing environmental pollution, air quality, microplastics, or pesticides are usually the first things that come to mind. However, scientists are increasingly drawing attention to another frequently overlooked factor—noise pollution. A new, large-scale study published in the scientific journal JAMA Neurology reveals a direct link between long-term exposure to traffic noise and the risk of developing Parkinson’s disease.
This unprecedented study conducted in Denmark monitored 3.1 million people over the age of 40 for 18 years. Based on national health data, researchers determined that for every 11.5 decibel (dB) increase in noise level on the most exposed side of a residence, the risk of Parkinson’s disease increases by 3%.
Parkinson’s is a progressive neurological disorder that damages specific regions of the brain, affecting movement and balance. According to scientists, chronic noise—particularly systematic sleep disruption caused by road traffic—increases levels of the stress hormone cortisol in the body. Constant stress and a lack of restful sleep are the very biological mechanisms that contribute to neurodegenerative processes.
Notably, the scientists also accounted for air pollution, and the study’s findings remained consistent regardless of the participants’ income or education levels. This significantly reduces the likelihood that the increased risk was solely driven by socioeconomic status.
However, the study also offers a reassuring detail: the presence of a “quiet side” in the home (a room located away from street noise) significantly mitigates the negative impact of traffic noise. Peter Chan, a senior researcher in environmental epidemiology at the University of Oxford, calls this fact interesting, noting that people can reduce their risks simply by moving to a different room.
