Endless - Georgia Straight

REBECCA BLISSETT PHOTO / JAMIE ROGERS MODEL
SAY WHAT?
COOL TECHNOLOGY MAY
BE AGING YOUR EARS
BY HELENA BRYAN
| GEORGIA STRAIGHT MIND BODY SOUL | | FALL 2005 |
6
young people everywhere likely have
Hip no idea that their oh-so-cool iPods and
other MP3 players could be hurtling them toward
middle age faster than driving the family
minivan. According to an expert in the area
of hearing amplifi cation at Indiana’s Purdue
University, the almost constant use of portable
music devices and cellphones by university and
college students may be behind a disturbing
increase in hearing loss in young people. In a
widely reported warning, Robert Novak, director
of clinical education in audiology at Purdue,
says the loss is comparable to that normally
seen only in middle-aged adults.
Novak is not the only one with serious concerns.
A long-term Argentinean study, the results
of which ran in the February 2005 issue of the International
Journal of Audiology, was designed
to explain the high percentage of the country’s
20- to 25-year-olds who failed pre-employment
medical examinations because of hearing loss,
despite having no history of ear disease.
The study pointed the fi nger at various sources
of recreational noise, including live concerts, stereos,
dance clubs, and portable music devices.
Vancouver audiologist Mark Hanson told the
Georgia Straight during a telephone interview
that he isn’t surprised by the fi ndings. “I see
more and more younger people in my private
practice concerned about hearing loss,” he
said. The surging popularity of portable audio
devices such as iPods increases the risk of hearing
loss for two reasons, Hanson said. They are
convenient, so people are listening to them
more often; and, because the earphones are inserted
right into the ear, they put more pressure
on the eardrum itself.
As assistant professor at UBC’s School of Audiology
and Speech Sciences, Navid Shahnaz is
not only an expert on hearing and hearing loss,
he witnesses enough campus culture to make
observations about the use of personal listening
devices. “It certainly seems widespread,” he said
from his UBC offi ce.
Recent UBC graduate Scott Lyon goes even further.
“There’s an iPod explosion,” he said in a recent
phone interview. “They are ever present and
omnipresent. And everybody who uses them
raves about them, so I don’t think they’re going to
go away anytime soon.”
The maximum decibel level on such devices is
usually 105, and the listener’s tendency is to turn
the sound on high to mask other noises such as
traffi c or conversation, noted Shahnaz. “I see students
getting on and off the buses with them on.
And buses are noisy, so they’re probably pumping
up the volume to the maximum.” Noise levels
aren’t helped by the hordes of cellphone users
who seem to feel they need to yell to be heard at
the other end.
Decibels are a measure of the pressure sound
exerts on a surface; that is, the intensity of a sound.
To put 105 decibels in perspective, consider that
the average conversation is 60 decibels, traffi c
noise is 80 decibels, and a power saw is 110.
According to Canadian occupational law—
which Shahnaz believes is too liberal as it favours
the employer, not the employee—the
allowable exposure limit without ear protection
for an 85-decibel sound is eight hours. He
pointed out that it wouldn’t be a stretch to think
that increasing the decibels just a little wouldn’t
hurt. But with every three-decibel increase, the
amount of pressure hitting the eardrum doubles;
and the allowable time without protection
is halved. So, at 88 decibels, the allowable exposure
time is four hours; at 91 decibels, it’s two
hours; at 94 decibels it’s one hour, and so on.
At 105 decibels, the allowable exposure time
is about four minutes—barely enough time to
hear out one whole tune.
“Even at the 85-decibel level, you’re causing
damage to the delicate hair cells in the inner
ear,” Shahnaz said. He likens these cells to
blades of grass. If people step on the grass a
couple of times, it will gradually stand straight
up again. But if they continue to tread on it, the
blades will eventually fl atten and won’t bounce
back. Likewise, a couple of noise exposures
won’t permanently damage the hair cells. But if
they are constantly bombarded, they’ll eventually
become detached, resulting in permanent
hearing loss because the cells don’t regenerate.
The ability to hear high frequencies—birdsong
for example—will go fi rst, gradually expanding
to the lower frequencies. In addition, a side effect
called tinnitus may take hold, in which the
hair cells themselves start to emit a ringing or
buzzing sound. At the very least, says Shahnaz,
tinnitus is an annoyance; at worst, it can disturb
sleep and lead to depression.
The impact of hearing loss goes well beyond
the ear, both Shahnaz and Hanson emphasize. It
can be socially isolating and affect performance
at school and work. Students with professors who
talk quickly or with an accent can suffer academically.
That romantic dinner for two might not be
so romantic when the words “I love you” aren’t
heard above the noise of the restaurant. And a
fi nancial planner or real estate agent who can’t
distinguish between a “two” and a “three” could
lose somebody a lot of money.
Apart from tossing their iPods and other portables
into the bin, how can kids protect their delicate
hair cells from permanent damage? Hanson,
who himself is not averse to using a Walkman when
he goes jogging, suggests using earphones—the
kind that sit on top of the ear—instead of the ear
buds that fi t inside the ear. They can also turn down
the volume. While that last piece of advice won’t
be music to the ears of most young rock fans, their
ability to hear the music they love so much may
very well depend on it. -