Earbuds used with the iPod and other music players can increase the risk of hearing loss, according to a US audiologist.

Dean Garstecki, of Northwestern University, said that an increasing number of young people were now experiencing the kind of hearing loss found in aging adults.

Low cost earbuds were more likely to increase the risk of loss in hearing than muff-type earphones, according to Garstecki.

The research found that MP3 users often listen to music at 110 to 120 decibels which can cause hearing loss after about an hour of listening. Because earbuds are placed directly into the ear, they cause damage by boosting the sound signal by as much as six to nine decibels.

Garstecki advised lowering the volume levels while listening to music. "If music listeners are willing to turn the volume down further still and use different headphones, they can increase the amount of time that they can safely listen," he said.

Noise-cancelling headphones are better because they reduce or eliminate background noise. But such headphones are often less popular because they are more costly and more visible than the tiny earbuds.