HOW DO WE KNOW WHETHER OUR CHILDREN’S HEARING IS BEING AFFECTED?
DURING the Covid-19 pandemic, have your kids been using headphones more than usual? Maybe for remote schooling, video chats with relatives, or for their favourite music and Netflix shows?
We have to be careful about both the volume and duration of headphone use. Listening to sound that is too loud or for too long can do permanent damage to hearing. The good news is there are ways to prevent long-term harm relatively easily.
HEARING LOSS IN CHILDREN MAY BE INCREASING
Our hearing needs to be protected throughout life, because damage to hearing cannot be reversed. This is why we have workplace noise exposure standards and guidelines, which tell workers when to use protection such as earplugs or ear defenders.
Unfortunately though, hearing loss in children may be increasing. A study from last year, in which both of us were involved, reviewed the hearing of more than 3.3 million children from 39 countries across a 20-year period. We found around 13% of children had measurable hearing loss by 18 years of age that may impact their ability to decipher sounds important for understanding speech. The study suggested hearing loss in kids is rising – but we don’t yet know why.
Not many studies have examined whether headphone use is directly linked to hearing loss in children. But in one study of 9- to11-year-old Dutch children, where 14% had measurable hearing loss, around 40% reported using portable music devices with headphones. Could headphones be contributing? Possibly, but unfortunately we don’t know for sure, and more studies are needed.
Adults typically first notice a hearing problem by struggling to hear higher-pitched sounds clearly. Sounds may seem muffled, or the ears may feel “blocked”, or they may notice a ringing or buzzing sound, called tinnitus.
Unlike adults, children won’t necessarily know how to describe these symptoms. Instead they may use terms they do know, like a bee buzzing, a whistle, or the wind blowing. Parents should treat any reported ear symptom as serious and get their child’s hearing tested. It’s best to visit a hearing clinic first, and then a GP if necessary.
EXCESSIVE NOISE DAMAGES HEARING
Exposure to loud noise can damage these hair cells and perhaps the nerve that connects the cochlea (inner ear) to the brain. Repeated excessive noise exposure can lead to permanent hearing loss. free sound meter apps that help with understanding the volume of different environments and activities.
Everyday conversation is around 60dB, which will not be a problem regardless of the duration of exposure. However, guidelines say we can be exposed an 85dB sound (like a rubbish truck) for up to eight hours at a time. But if the loudness of the sound is increased by just 3decibels to 88dB, the sound energy is doubled, and safe exposure time would drop to just 4 hours. Exposure to noise is cumulative. Noise can also come from other sources.
Parents should try to avoid consecutive noisy exercises, like headphone use, music practice, then noisy toys or games. Considering the total “doses” of sound in the day means parents should schedule some breaks to allow the ears time to recover.
Carew is a lecturer at University of Melbourne and Sung is a paediatrician, Senior Research Fellow, Honorary Clinical Associate Professor, Murdoch Children’s Research Institute