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Transcript
iPod Ear and the 'Huh? Wha?' Generation
By Jodi Mailander Farrell
The Miami Herald
12/17/08 4:00 AM PT
iPods and other portable MP3 players aren't the first things to cause hearing loss, but they're being blamed for
an uptick in hearing damage among teens. Walkmans rattled their fair share of eardrums in the '80s, but today's
music players have longer-lasting batteries and hold enough tunes to keep the music pounding all day.
They're called the "iPod Generation" -- all those kids wired to earbuds and MP3 players this holiday season as
they hunker down to endure long road trips or relatives that visit even longer. But they're at risk of becoming
the "Huh? What?" Generation.
You've heard of BlackBerry Thumb? Now there's iPod Ear.
With the increasing popularity of MP3 players -- and the loud, long listening habits of today's youth -- millions
of children and teens are at a newfound risk of noise-induced hearing loss. Doctors here and around the country
say they are seeing younger and younger patients with hearing loss symptoms that typically don't occur before
middle age. Many of them blame constant use of iPods and other players that blare music directly into ears.
Similar concerns were raised with Sony's (NYSE: SNE) Walkman in the 1980s, but the difference is that the
latest portable stereos hold thousands of songs and have longer-lasting batteries. Because hearing damage is
directly related to the duration of exposure -- not just volume -- one fear is that steady, long-term exposure to
even moderately loud music could result in premature hearing loss.
"Once these things became portable and full-time usable, we really started noticing more noise-induced hearing
loss problems in younger children," said Dr. Robert Fifer, director of Audiology and Speech Pathology at the
University of Miami's Mailman Center for Child Development.
"We're seeing the same kind of hearing loss we used to see in older people who worked in factories for years."
Noise-Induced Hearing Loss
Hearing specialists say the cases they're seeing may be only the beginning for this generation because
accumulated noise damage can take years before it causes noticeable problems. The research isn't conclusive,
but the warning signs are there:
The number of Americans age 3 and older with some form of auditory disorder has more than doubled since
1971, from 13.2 million to about 30 million today, according to the American Speech-Language-Hearing
Association. Of those, one-third are said to have noise-induced hearing loss.
The Centers for Disease Control and Prevention reports that 13 percent of American children between 6 and 19
-- more than 5 million young people -- have some form of noise-induced hearing loss.
More than half of American high school students have at least one symptom of hearing loss, according to a
2006 poll by the American Speech-Language-Hearing Association. Hispanic teens, in particular, are at risk
because a greater proportion of them play their iPod at loud levels and listen longer (one to four hours),
compared with other teens.
In October, the European Union's Scientific Committee on Emerging and Newly Identified Health Risks
reported that 5 to 10 percent of personal music player listeners risk permanent hearing loss if they listen for
more than one hour per day each week at high volume settings for at least five years.
What's Too Loud?
At peak volume, iPods can hit close to 120 decibels -- a level between a jackhammer and a jet engine. Hearing
experts say 85 decibels -- the sound of city traffic -- is safe. An MP3 player's range is usually 60 to 110
decibels. But too many people are going beyond the recommended limits, especially when they're on the street
or in crowded places and crank the volume to drown outside noise.
Another alarming trend: Toy manufacturers are marketing MP3 players to children as young as 3. These devices
-- Bratz Liptunes, the Disney (NYSE: DIS) Mix Stick -- produce sound well above 85 decibels, according to an
analysis by the American Speech-Language-Hearing Association, which says this is like "plugging virtual rock
concerts" into toddlers' ears.
Hearing specialists say the cases they're seeing now may be only the start of trouble for this generation because
accumulated noise damage develops slowly and insidiously. A 15-year-old who regularly cranks the volume on
his player for hours at a time may not experience any noticeable problems until he or she is in their mid- to late20s.
As part of a "Turn It to the Left" campaign, the American Academy of Audiology has produced a rap song that
warns kids to turn the volume down on their MP3 players:
Ahh, It ain't no funny, man, it ain't no fun, when you're 20 years old, but your ears are 81.
Fifer says he's seen early signs of noise-induced hearing loss in his patients between 8 and 16.
"The common denominator is the iPod or other similar device," he said. "They like to listen to it loud, usually
so loud that mom can hear it across the room. The general rule of thumb I give them is that they should be able
to hear the conversation around them. If not, it's too loud."
A Muffled World
Noise-induced hearing loss makes it difficult to understand what is being said in restaurants and other places
with background noise. Conversations sound muffled, as if coming through a hotel room wall. It also becomes
difficult to hear high-frequency, soft consonants, such as s, t, f, h and the sh sound.
"In English, those sounds comprise more than one-third of what we speak, so you're talking about
misunderstanding key words," Fifer said.
Dennis Burrows, a vice president with the American Speech-Language-Hearing Association, calls noiseinduced hearing loss a "quality of life issue."
Sufferers tend to withdraw, their health often deteriorates and they can encounter problems communicating at
work.
"Think of the older person with hearing loss; he's the one alone in the corner who is all crabby, but if people
lose their hearing at an earlier age, these flaws are going to kick in earlier," Burrows said.
Delicate Workings
Noise-induced hearing loss happens when loud sounds stress and damage the delicate hair cells in the inner ear
that convert mechanical vibrations in the air into electrical signals the brain interprets as sound. If exposed to
loud noises for a long time, the hair cells can die, producing hearing loss.
Views differ slightly on what are acceptable levels and durations for listening to a player. One 2006 study by
the University of Colorado at Boulder and Children's Hospital in Boston determined that a typical person can
safely listen to an iPod for 4.6 hours per days at 70 percent volume. The report found no significant difference
in sound levels between genres of music.
Complicating the issue is that not everyone shares the same risk of hearing loss. Some people have tougher ears,
while others are more tender and prone to damage. Also, unlike speedometers on cars, most MP3 players don't
warn you when danger levels are reached.
Audiologists tell listeners to subscribe to two basic rules of thumb: Keep the volume down (a good guide is to
set the volume level at half) and limit listening time (to give your hearing a break).
"If you can't hear someone speaking to you and that person is just an arm's length away, then your iPod is too
loud," Burrows said. "You don't have to understand every word being said, but you have to know someone is
talking."
Many hearing specialists also recommend replacing standard earbuds with more expensive noise-canceling
headphones or "canalphones." And Sony, Panasonic, Etymotic Research, Shure and Bose produce sets that aim
to block out background noise, so you can hear the music better at lower volumes.
But don't rely on just specialized earphones for safety.
"The problem is that no matter how you put the sound in, loud is loud is loud," said Burrows, 54. "It can be like
sticking a chainsaw in your ear. The real key is to watch your volume and limit your time.
" I'm an old Led Zeppelin rocker kind of guy and I crank it up sometimes. But I don't listen to it long. If I'm
going to really rock out, I do it for no more than an hour."
© 2009 McClatchy-Tribune Information Services. All rights reserved.
© 2009 ECT News Network. All rights reserved.