We often hear about pollution coming from cars, planes or plastics, but what about sound pollution? Sound pollution is the propagation of sound that affects our environment and ourselves in a number of different ways. This source of noise is usually caused by transport such as cars, planes or trains, machines, and propagation systems. Have you ever noticed the amount of noise you hear in a day? From your alarm clocks , to cars, trains, planes, road works…. Large amounts of noise have huge impacts on our lives and the lives of other living things around us. We have all experienced times when noise bothers us immensely. It has even been proven that being exposed to excessive and persistent amounts of noise can make one sick, or even depressed due to stress.
What exactly does noise pollution do to us, as humans? Noise has multiple effects on us, whether it is health, economy, territory and socially, noise has a persistent effect on us. However the gravity of this effect changes with the frequency and intensity of the sound. For every noise we hear, our bodies put us in a state of awareness and make us alert. Depending on the amount of sound, our stress hormones are produced, our heart beats faster, we sweat and our breathing quickens. But noise becomes most conspicuous when we sleep. In the case of nocturnal noise, an average of 40-50 decibels prevents sleep and only 35 decibels is needed to wake someone up.
But to what extent is this issue relevant to us in Switzerland? A report done by the European Environment Agency shows that at least 2.5 million of inhabitants of Switzerland’s 13 largest cities are exposed to noise levels above 55 decibels caused by road noise. Quoted from an article on lenews.ch “The cities with the highest percentages of residents affected by road noise over 55 decibels are Geneva (77%), Lausanne (74%), Basel (66%) and Lugano (65%). The figure for Zurich is 62%.” This study only looks at road noise, but if trains, planes and other things were taken into account, the amount of inhabitants would increase enormously. These high amounts of noise can highly affect one’s health, and it has. Illnesses such as cardiometabolic diseases, like hypertension, coronary heart disease, heart attacks, cardiovascular accidents and diabetes can all be caused by excessive exposure to noises of high intensity.
Now this only shows us how sound pollution affects us, but how does it affect animals and our environment? A study made by the CNRS (Centre National de la Recherche Scientifique) and the university of Lyon studied how sound pollution affected green tree frogs. Because of sound pollution communication between a lot of different species of animals has been limited, the common green tree frog included. Sound pollution created by road noise has affected them highly. Because of noise, they are subjected to stress which affects their health status, in particular the coloration of the vocal sacs of male green tree frogs, a coloration which allows females to spot them. If this continues, and road noise persists in bothering this species, it could have a direct impact on the way they breed, and on a larger scale, this could lead to the extinction of the species.The impact of noise pollution on animal health thus appears much greater than previously thought, and potentially affects all vertebrate species who are exposed to high intensity noises, such as the road. Infact, a recent report done by the WWF, published on the 10th of September 2020, warns us that over 68% of all vertebrates have disappeared within the last 50 or so years due to human activity. Noise pollution has without a doubt been a factor of this terrifying number.
Sound pollution also highly affects marine life. A study was made by biologist and engineer Michael André, director of the Laboratory of Bioacoustic Applications of the Polytechnic University of Catalonia. He explains that sound pollution for aquatic animals is a huge problem. At the bottom of all large bodies of water, different sound sources coming from various human activities can disturb underwater life. These include: Gas and oil prospecting, military maneuvers, shipping boats, touristic and leisure boats and even the construction of wind turbines, all affect marine life. Marine mammals like dolphins and whales use echolocation, sounds to communicate, are sensitive to this noise pollution. But not only large mammals are affected by this. Any type of fish or marine life is affected by it. If any is exposed to a large noise of very high intensity, the trauma can lead them to completely stop eating and moving. This unfortunately leads to a slow and painful death. Since this affects pretty much all marine life whether it is in oceans or lakes, this should logically have an effect on lake life in the Lac Léman, where there is a great deal of human activity.
Scientists have also discovered that turtledoves have been highly affected by noise pollution. In areas of high noise frequency, as they are unable to modify the low frequencies of their repertoire, they have deserted the edges of woods that are located near highways. Forests see the diversity of their species reduced as pollinating birds like the turtledove have left and no longer disperse seeds highly affecting the rest of the species.
However the most appalling news of all, is that noise pollution often takes place in nature reserves. In “Les Bois de Versoix”, a protected area surrounded by highways and an outdoor shooting range, noise resonates throughout the forest for several kilometres, so even the animals far away will be affected. The average gunshot is between 140-165 decibels, and the sound can travel up to 1.6km. Often animals experiencing such loud noises on a regular basis can find themselves disoriented and unable to find food. In the case of deers, it has occurred that they lose their herd. “It has now been proven: human noise can prevent an animal from hearing other important sounds, which allow it to move, to look for food, to defend its territory, to avoid predators, to attract a partner or maintain social groups, explains Rachel Buxton a conservation biologist at the University of Colorado and lead author. By changing the behavior or distribution of key species, entire ecosystems can be affected by noise.”
Noise pollution is unfortunately not a topic that is spoken about often, however it is extremely relevant to our society in Switzerland. The importance of the impact of noise pollution needs to be a more publicized topic and as much discussed as climate change, for instance. So let’s raise awareness.