Any man-made sound that penetrates the environment is noise pollution. Noise pollution can be caused by highways, factories, concerts, or any other noise source. It can interfere with the natural cycles of animals, who may change their migration paths to avoid the sound. Perhaps the most extreme damage caused by noise pollution is the death of marine mammals by the rupturing of various tissues and organs, brought on by extremely loud (up to 200 decibels) sound from military SONAR.
