• Preventing hearing loss induced by recreational exposure to sounds 

There is a risk of irreversible noise-induced hearing loss due to recreational exposure, especially among adolescents and young adults. 

• Nearly 50% of teenagers and young adults (12-35 years of age), which accounts for 1.1 billion young people, are at risk of hearing loss due to prolonged exposure to loud sounds, through listening to music on smartphones and audio players or at music gigs and clubs 
• Among those aged 12-35 years living in middle and high-income countries, nearly 50% are exposed to unsafe levels of sound from the use of personal audio devices 
• Around 40% of 12-35 year-olds are exposed to potentially damaging sound levels at clubs and bars 
• Promoting and practicing safe listening is one of the simplest ways to prevent the occurrence of hearing loss that is caused by recreational exposure to loud sounds 

According to global data, over 5% of the world population lives with hearing loss and the majority of this population live in low and middle income countries. Exposure to loud sounds may occur in occupational, environmental or recreational settings. With the current lifestyle with increased recreational sounds and usage of earphones and hands-free devices, the percentage of the population with hearing loss is predicted to increase in the coming years. Even though the prevalence of hearing loss increases with age, current data suggests that the younger generation is becoming more vulnerable for hearing loss mainly due to the increase in recreational sounds. The World Health Organisation (WHO) has declared 3 March as “World Hearing Day” each year and it was celebrated this year featuring the theme “To hear for life, listen with care”, to focus on the growing risk of hearing loss in recreational settings.  Dr. Sithara Dissanayake, Consultant ENT surgeon and Senior Lecturer in the Faculty of Medical Sciences, University of Sri Jayewardenepura shared her expertise about the topic. Dr. Dissanayaka also holds the position of the scientific secretary of the College of Otorhinolaryngologists and Head and Neck Surgeons of Sri Lanka. Following are excerpts from the interview with Dr. Sithara Dissanayake:  What do you mean by unsafe listening? Generally, listening to sounds more than 80dB in intensity for a duration more than 40 hours per week is considered unsafe. However, if the sound intensity is high, hearing loss could occur even during exposure for a shorter period of time or vice versa. Loud noise causes hearing loss by irreversibly damaging the hair cells in the inner ear. Loss of hair cells lead to permanent hearing loss. This condition is called the noise induced hearing loss. Who is at risk of developing noise induced hearing loss? Exposure to loud noises could be an occupational hazard for people who are working with heavy machinery. However, recent studies have shifted into evaluating noise induced hearing loss caused by recreational activities such as listening to loud music through headphones and earphones. Studies have revealed that 50% of young generation between 15-35 years, use portable audio devices with audio levels set at a sound level above safe limits. The average listener keeps the volume intensity of their head/earphones between 75-105dB. Hence, if a person listens to 100dB for even 15 minutes per day it is sufficient to cause damage to hearing.   This is becoming a major concern worldwide as it is the younger generation who is at risk. Environmental factors such as the long-term exposure to noise on the roads due to traffic could also lead to noise induced hearing loss. Environmental factors often may not be very severe enough to cause irreversible hearing loss. However, it could cause other unwanted effects such as high blood pressure, ischemic heart diseases, poor sleep and impairment of cognition.  Why are we worried about it at this moment? The Covid-19 pandemic has shifted education from a physical classroom to a virtual one. Hence, children have the access to electronic devices from a very young age and some would use ear/headphones when using these devices. Even after the classes they often use the phone for their recreation activities such as listening to music, watching cartoons and playing games. If the sound levels are set at a higher level or the time duration is longer, these children are highly susceptible for permanent hearing loss.  Listening and comprehension are corner stones for good communication. Therefore, when hearing is impaired, following conversations and expressing their opinions would be difficult. The use of masks and social distancing also adds to the problem by removing the non-verbal cues. Hence these children can gradually become frustrated and socially withdrawn. If very young children (example: pre-school, nursery) are affected they may not develop the full vocabulary and will have a language deficit. Therefore, we all should be vigilant to prevent the future generation from having impaired cognition, bad relationships, poor mental health, poor education, unemployment and many other problems. Hence, safe listening is a noteworthy topic at this moment.  How can someone suspect to be having noise-induced hearing loss? If the hearing loss is mild the patient may not recognise that they are having hearing impairment or they may recognise it only in crowded noisy environments. This is because the noise initially damages the cells involved in hearing of high frequency sounds. However, as the damage progresses the severity of the hearing impairment will also worsen.  Tinnitus, which is the experience of ringing or other noises in one or both ears, is another symptom of noise-induced hearing loss. It is a sensation of sound in the absence of any external stimuli. Often the patient may feel as if there is an insect producing sound in the ear.  Hidden hearing loss is also an entity identified with noise exposure. It is called hidden as there will be no documented hearing loss on standard hearing tests. Irrespective of the symptom, children who are having noise-induced hearing loss are more prone to have age-related hearing loss later in life. How do we practice safe listening? 

• Reduce the volume: The volume of the device should not exceed 60% of the maximum volume. Parents should make sure that all audio settings are below this level when younger children are using devices. If earphones are used, they should be properly fitted for enabling them to hear better without increasing the volume 
• Protect your ears from loud noise: Simple measures such as wearing ear plugs or moving away from the source of the sound (example: loudspeaker) could protect ears from noise induced hearing loss 
• Limit time spent in noisy environments: Take a break, limit the time spent on audio devices. If staying in a noisy environment (example: music studio, bar etc.) take breaks in a quiet place. Most of the time children may not be aware of safe listening. Hence, it is our responsibility to educate them 
• Monitor sound levels: There are smartphone applications to monitor sound exposure. When choosing smart devices, it is better to choose devices with in-built safe listening features 

(The writer is a Medical Officer at the Directorate of Healthcare Quality and Safety at the Ministry of Health)