Unwanted sound is considered as noise pollution which can cause both behavioral and health problems in human beings. Noise pollution can cause physiological changes in the body like hypertension, high stress level, sleep disturbances etc. It can also cause behavioral changes like annoyance, aggression etc. Normal pleasing sound level is around 30 dB but the normal environmental noise is around 40-60 dB which can be considered as normal. But if the noise level increases above 80 dB, it can affect our psychomotor performance and creates high stress level, loss of attention, physiological changes etc.
Noise pollution can cause many detrimental changes in animals and increase the rate of mortality by changing the delicate balance of prey-predator relationships. Noise interferes with the use of their own sound for communication related to reproduction and migration. Overexposure to high intensity sound affects the hearing ability of many animals. Very high sound causes the reduction in the number of animals in the habitats leading to habitat loss and may lead to the extinction of species.
Impact of noise pollution is very high in industrialized areas and metropolitan cities compared to other parts. Elevated noise in factories, workplaces can cause hearing impairments, hypertension, annoyance, sleep disturbances, decreased attention in children etc.