Loud music hurting kids’ hearing

Studies in NZ and Australia find listening habits on smartphones creating long-term damage to children’s ears

Noise-induced hearing loss is on the rise amongst children as studies show listening to loud music can be just as addictive as smoking. Dr David Welch, head of Auckland University’s audiology department, says research shows about 14 per cent of children may have noise-induced hearing loss as a result of prolonged exposure to personal listening devices, while new Australian research has yielded similar findings.

Welch is speaking out as holidays loom, with children likely to be spending more time on their phones.

He’s urging parents to keep an eye on their child’s digital device use.

People with hearing impairment from listening to loud sound may have a measurable loss of hearing in a range of frequencies, but may also have impaired perception of sound in noisy environments, Welch said.

“This may occur alongside tinnitus, or ringing in the ears,” he said.

Change was needed at a societal level with better awareness of the permanent damage happening.

“We can draw a parallel with smoking, which is also harmful behaviour, but one that as a society we’re just not accepting any more,” Welch said.

“We are much more tolerant of loud music even though we know it causes a permanent injury which can destroy our lives and cut us off from the people we care about.”

The maximum safe level for prolonged listening was considered to be 85 decibels — with most smartphones capable of producing volumes of up to about 120 decibels. “The general trend appears to be that devices like smartphones are getting louder over time — with the latest model from one of the most popular brands capable of producing 25 per cent higher volume than its predecessor,” he said.

When volume increases beyond 85 decibels, the threat to hearing rises. After two hours of listening to a device at 91 dB the child has had exposure similar to working a shift in a noisy factory where hearing protection would be required by law.

“Parents [should] look at ways to limit the amount of time their children spend listening to loud music, whether it is in the car, at concerts or on devices.”

Welch says hearing was damaged through apoptosis, where noisedamaged sensory cells in the inner ear will shut down and kill themselves so they can’t cause more harm.

“This process causes scarring which prevents new cells growing . . . The nerve fibres that convey information from the ear to the brain are also thought to be threatened by exposure to loud sound. We are worried that this could become an epidemic of the digital generation.”

Meanwhile, a study at National Acoustic Laboratories in Macquarie University’s Australian Hearing Hub paints a grim picture for users of smartphones and MP3 players.

“We found that 41 per cent of participants reported feeling they have a hearing loss, with 20 per cent reporting difficulties with speech in noise,” said lead author Dr Megan Gilliver. For 18- to 35-year-olds, higherrisk status was linked with a greater proportion of such self-reported hearing difficulties, including perceived poorer speech perception.

Researchers found the youngest age group of 15- to 19-year-olds listened to listening devices for an average of about 88 hours a month. The hours decreased by each older group.

The results indicated that while most Australians were listening responsibly, many needed to either drop the volume — down to 80 per cent — or listen for a shorter duration, 1.5 hours, to reduce the risk of experiencing hearing difficulties.

Puro Sound Labs distributes children’s headphones which automatically restrict maximum volume.

Owner Lee-Ann Verry said she began importing the product after becoming concerned about her own children’s digital device use.