According to new research, nine out of 10 city-dwellers are exposed to enough loud noise that it puts them in danger of hearing loss.
But where does the damaging noise come from?
Surprisingly, it comes more from MP3 players and stereos, than it does from the rattling, rumbling subways or loud, booming workplaces and construction sites, researchers found.
That's not to say that transit and work-related noise didn't account for some of the damaging noise levels -- the study shows that one in 10 people who use public transit were exposed to noises that go above the recommended limits, just from the public transit alone.
But when researchers looked at the total exposure to noise over a year by city-dwellers, they found that most are exposed when they listen to their MP3 players and stereos. Ninety percent of public transit-users and 87 percent of non-transit users are exposed to damaging noise levels mainly from using their MP3 players or stereos.
"I do think it's a serious problem, there aren't really any other experiences where we would tolerate having nine out of 10 people exposed at a level we know is hazardous," study researcher Rick Neitzel, an assistant professor in the University of Michigan School of Public Health, said in a university statement. "We certainly wouldn't tolerate this with another agent, such as something that caused cancer or chronic disease. Yet for some reason we do for noise."
Researchers conducted their study in 4,500 New York City residents. They found that on average, an NYC transit user spends 380 hours waiting for or riding the subway or bus, which has noise levels of 72 to 81 decibels. (As a comparison, speaking level is 60 decibels, a bustling street corner is 80 decibels, a circular saw is 90 decibels, a crying baby is 115 decibels and a noise level that induces pain is 125 decibels).
In addition to damaging noise, city-dwellers are also -- for whatever reason -- more prone to mental disorders like schizophrenia than people who live in quieter villages and towns. That research, which came out this year, was published in the journal Nature.