In fact, noise causes discomfort and stress that disrupts human or animal organisms. In Man this can cause problems of irritability, insomnia and depression. Animals tend to escape, whenever possible, from areas that are too noisy.
Species that use sound to orient themselves, move and communicate, such as cetaceans or bats, are particularly vulnerable to this type of pollution.
When sound levels are too high, the noise can cause physiological damage with a temporary or even permanent loss of hearing.
In light of these effects, national laws tend to impose noise exposure threshold limits for the population and environment, perform impact studies and implement relief and protection measures (e.g. noise barriers, individual protection).
All the same, this physical type of pollution does not persist in the environment. Once the source of noise is eliminated, there are no new effects.
The areas around airports are exposed to noise pollution, to the great displeasure of local residents. © Douchet Quentin, Wikimedia CC by-sa 3.0