Clinical audiologist Ken Rubenacker of Sikeston said even more disturbing pattern is that noise-induced hearing loss is now being seen among adolescents and teens.
"The rapid growth in use of music type devices such as the iPod is felt to be a contributing factor in this increase," Rubenacker said.
More than half of high school students and adults surveyed recently reported at least one symptom of hearing loss according to a poll commissioned by the American Speech-Language-Hearing-Association.
The survey, which examined the use of new popular music devices like MP3 players and iPods, gauged awareness of noise-induced hearing loss. Experts said users of portable music players and other popular technology listen to devices too long at high volumes.
The polling found that high school students are more likely than adults to say they have experienced three of the four symptoms of hearing loss: turning up the volume on their radio; saying "what" or "huh" during normal conversation; and having tinnitus, or ringing in the ears.
Portable music players are in the spotlight for potential hearing loss, but Dr. Timothy Hullar, an otolaryngologist at Barnes-Jewish Hospital in St. Louis, said they're OK if not overdone.
"Certainly if you play an iPod at a reasonable level you could play it all day or night for years and you'd never lose any hearing at all," Hullar said. "As soon as you're experiencing loud music or loud sounds in the space of a couple hours, you're inducing what could be permanent damage."
More than 20 years ago OSHA established standards of controlling exposure to excessive noise levels in the workplace. The standards required employers to provide annual hearing evaluation to monitor hearing levels, as well as providing appropriate hearing protection to employees in work situations with noise levels in excess of 85 decibels.
No such regulation has yet been applied to recreational listening, such as listening to music, etc., Rubenacker noted.
In March, Apple -- the maker of iPod -- introduced a free software update that gives iPod users the ability to set maximum volume limits on the device. Using a combination code, the update allows users and parents to set volume caps on the iPod and lock them in. The new volume limit update works with all earphones and accessories plugged into the iPod headphone jack as well as the iPod Radio Remote. The software update is available as a free download for the iPod nano and fifth generation iPod. Users can download the free updates at www.apple.com/ipod/download.
But very seldom do customers inquiring about iPods worry about damaging their hearing, an associate with Best Buy in Cape Girardeau said.
"We ask if sound quality is important to them, and outside of that, the only issue is whether they'll play loud enough or if they can hear it when they drive a motorcycle or mow the lawn.
"Most people that come in to buy an iPod are already familiar with it because they know someone who has one, and they've seen enough where they're familiar with them so they don't ask too many questions," the associate said.
Locally, it's both the adults and teens who use the portable music players, the Best Buy employee said.
"Noise-induced hearing loss occurs when loud sounds result in damage to the hearing nerve, or cochlea. Unfortunately, this type of hearing loss is almost always permanent in nature, and is generally not amenable to medical treatment," Rubenacker said.
To help prevent hearing loss, audiologists recommend listeners keep the volume down, limit the time listening to a player, custom-molded ear sleeves are available for some of these products, sound isolating earphones are available at music stores and elsewhere and consider upgrading your earbuds to sound isolating earphones.
If a friend or loved one has their iPod so loud, it can be heard from a few feet away, tell them to turn it down for the sake of their own hearing, Hullar said.