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From a blackbird's song to the rumble of a passing train, sounds are produced by vibrations (振动) moving through the air, ground, or water in invisible waves. When those soundwaves enter your ear, they make tiny membranes, bones, and hair cells inside vibrate, which triggers electrical signals that your brain interprets as sound.

But when that sound is extremely loud or frequent, it can actually harm the human body. "You can be exposed to so much sound that it destroys your hearing," says Erica Walker, an epidemiologist at Brown University. As volume increases, the length of time during which you're exposed to it should decrease.

It's one thing to leave a concert with ringing ears or to be surprised by a sudden loud noise, but how does that actually affect your health? "When that stress response is stimulated, you start to breathe faster. Your heart rate starts to increase," says Walker.

If this happens once or twice it might not be that big of a deal, but over time, constant stimulation of your body's stress response, or long-term noise exposure, can make you more likely to develop serious health problems. According to one estimate, long-term noise exposure leads to 48,000 new cases of heart disease in Europe each year and affects the quantity and quality of sleep for 6.5million people. Noise can raise your blood pressure and heart rate even while you sleep.

But there can also be a psychological aspect, especially if people feel like they have no control over the noise they are exposed to. This can lead to mental health harms, such as increased anxiety and depression, says Walker.

When it comes to sleep, noises don't have to be nearly as loud to cause problems. According to Jackson, sounds as low as 30 to 40dB can cause a person to toss and turn or wake up. However, sounds in this range are only associated with modest health effects. It's really when you see night noises in the range of 40 to 55 dB or more that negative health effects are observed.

To keep noises from ruining your sleep studies suggest playing white noise through the night can help mask other sounds. Experts also suggest modifying your bedroom to safeguard against nighttime noise. "Add soft surfaces that help block or lessen noise, such as wall decorations, acoustic tiles, or a thicker bedroom door," says Jackson.

However, the best way to fight back against noise pollution is to focus on the source. We need to think about how to change that going forward.