Headphones increase risk of hearing loss

By strolling across any college campus, one can see just how commonplace it is for students to listen to music as they read, study, exercise or work.
It is highly probable there is a college student with earbuds reading this right now.

Recent research shows using headphones to listen to music on an iPod, MP3 player or cell phone can damage hearing.

An Aug. 18 article in “The Journal of the American Medical Association” stated scientists reported hearing loss in teenagers rose about one-third from 2005 to 2006 compared with the rate from 1988 to 1995.

These findings indicate as many as 6.5 million U.S. adolescents, 12 to 19, now have hearing loss.

This increased rated of headphone usage is causing more noise-induced hearing loss in teenagers and young adults, according to researchers at Purdue University in Indiana.

Robert Novak, Purdue’s director of clinical education in audiology, believes listening to music has become more of a full-day experience than it has been in the past. Novak said he is seeing an invasion of young people with “older ears on younger bodies.”

Long-lasting rechargeable batteries with iPods and other portable music players that have the capacity to hold hundreds of songs are making this possible.

Nowadays, people of all ages are listening for greater amounts of time and not allowing their ears enough time to rest and recuperate.

University student Roosevelt Stanley Sinclair III, a senior science major, said he has observed many students on campus using headphones.

“I walk by the same people every day listening to music with earbuds, and I can hear their music,” Sinclair said. “I think it’s unhealthy. It could burst your eardrums.”

The volume measured in decibels and the length of exposure time are important considerations when listening to music or any other noise for that matter.

Senior Beayonka Askew,  a University health-studies major, said she has used earbuds to listen to music and frequently has to adjust the volume levels because some songs play louder than others.

“I usually don’t listen very long at a time or with it very loud because I had ear tubes put in when I was younger,” Askew said. “I don’t have really good hearing to start with, so I’m more susceptible to hearing loss.”

Another important factor, one that many people do not take into account, is the quality of earphones they use.

Generally, the earphones that accompany your mobile device—iPod, MP3 or cell phone—usually are not of the highest available quality. Their range of frequencies is quite limited and can cause you to strain your ears.

Earbuds and some headphones have another disadvantage as well.

Neither allows the air in the ear canal to move freely, which also places strain on your ears.

“If earbuds are jammed into your ears, they seal off the sound in your ears,” Janice Richbourg, a Tyler doctor of audiology at ENT Associates of East Texas, said. “We are recommending custom-made earbuds, which allow some sound to come out through a vent hole.”

A study of young iPod users at Colorado University and Children’s Hospital in Boston led researchers to conclude that young people play music louder than adults often without realizing just how loud they are playing it.

Cory Portnuff, a Colorado audiologist who led the study, believes most people do not comprehend the degree of risk in which they are placing themselves by doing so.

“Noise exposure is time-weighted,” Richbourg said. “The louder noise is, the less time you can safely listen to it. If listening for a long time, it should be at a softer level.

Richbourg said while one can listen to 125 decibels of noise safely for only 25 minutes, the time increases to two hours of safe-listening time for 100 decibels.

She said one can spend eight hours safely listening to 85 decibels of noise and anything below that is not really damaging.

To explain this in other terms, Portnuff’s documentation states listening to music with earbuds at 80 percent volume for 90 minutes per day is probably safe for long-term hearing.

Of course, lowering the volume is better; so by decreasing the volume level to 70 percent, one can increase listening time to four-and-one-half hours per day.

Researchers at Boston Children’s Hospital disagree. They believe the volume should not be higher than 60 percent, and one should limit listening time to only one hour per day.

Although all types of noise surround us for many hours of the day and night, exposure to harmful sounds damages the auditory, or hearing, nerve and the hair cells resulting in noise-induced hearing loss.

The hair cells located in the inner ear play an important part in our hearing process, as they are responsible for transforming sound energy into electrical signals that travel to the brain. Damaged hair cells cannot grow back.

In the past, scientists once thought the sheer force of vibrations from loud sounds brought about the damage to hair cells, but recent studies negated those findings, according to ihearsafe.com.

Instead, they found harmful noise generates the formation of molecules within the ear that can damage or kill hair cells.

Two types of noise can trigger this damage: harmful impulse noise, such as an explosion, or loud sounds over a prolonged period of time, such as music or a chainsaw.

Richbourg said she and her associates are seeing more young people in the Tyler area with noise-induced hearing loss caused from impulse noise.
“We see young people who have damaged their hearing from not wearing earplugs while hunting,” she said.

Richbourg said she has not noticed an increase in young people with NIHL due to listening to music with earbuds because that type of hearing loss is a gradual process taking years to occur.

Portnuff said about 7 to 24 percent of iPod and MP3 users are listening to music at maximum volume levels. He said just five minutes of doing so can increase the risk of permanent hearing loss.

A real risk of hearing loss in the future exists for anyone who plugs in headphones to listen to music for too long and too loud, Portnuff said.