TEENAGERS and twenty-somethings risk going deaf up to 30 years earlier than their parents because they listen to music on MP3 players such as iPods at high volume for lengthy periods.

A study by Deafness Research UK suggests that young people who listen constantly to personal stereos through headphones are permanently damaging their hearing. Most are unaware of the danger, the charity found.

More than 50 per cent of those aged 16 to 24 listen to their MP3 players for more than an hour a day, and almost 20 per cent spend more than 21 hours a week plugged in, according to the survey. But 68 per cent of the group do not realise that listening to a music player at loud volume can cause lasting damage.

Vivienne Michael, the chief executive of Deafness Research UK, said: “A generation ago we would see people going deaf in their sixties or seventies, but we’re now seeing more people going deaf in their forties, which is very worrying.

“Many young people are regularly using MP3 players for long periods and are frighteningly unaware of the fact that loud noise can permanently damage your hearing.”

Ms Michael said that, despite warnings from the Health and Safety Executive that any noise above 105 decibels can permanently damage hearing, the maximum volume on many MP3 players was up to 120 decibels — “as loud as an ambulance siren”.

Loud noise kills off hair cells in the ears that pick up sounds and help to process them. These cells gradually die anyway in old age, but exposure to loud noises accelerates hearing loss.

Ms Michael said that people needed to be aware that the louder a noise, and the longer the exposure to it, the more hair cells were destroyed; the deterioration was irreversible.

The charity advises a “60-60 rule”: MP3 users should not listen to music at more than 60 per cent of the maximum volume or for more than an hour. She said that if your music is so loud that other people can hear it, it is too loud.

“Hearing loss can make life unbearable,” she said. “We want people to realise that their hearing is as important as their sight and protect their ears against any potential damage. We don’t want the MP3 generation to go deaf in their thirties or forties.”

The survey also showed that a third of people under the age of 35 had experienced ringing in the ears — a sign of hearing damage — after listening to loud music. Four out of five in this group also went to noisy nightclubs.

The Royal National Institute for the Deaf endorsed the warning about MP3 players. John Low, its chief executive, said: “New technology and ever- increasing storage capacity enables people to listen non-stop for hours and at louder volumes than ever before. If you are regularly plugged in, it is only too easy to clock up noise doses that could damage your hearing for ever.”

• A touch-screen computer system that helps people to check their hearing using calibrated headphones is to be made available on the high street.

  The optical company Specsavers plans a £1.5 million programme to introduce the hearing screening in selected stores over the next five years. A similar test, which involves listening to a series of “pure tones”, is available through the NHS.

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