As Bluetooth earbuds use increases, the number of patients with hearing loss is steadily increasing. According to the Health Insurance Review and Assessment Service (HIRA), the number of hearing loss patients in Korea increased annually from 548,913 in 2017 to 742,242 in 2021. Among them, young people in their 30s or younger accounted for 19.7% of the total.
  Noise-induced Hearing Loss (NIHL) refers to hearing abnormalities caused by loud and continuous sound stimulation. NIHL symptoms in young people are increasing every year. It is pointed out that the use of sound devices such as Bluetooth earbuds has increased, and the frequency of noise exposure has increased among young age groups. Earbuds deliver sound directly to the ear, so care should be taken when using them for a long time.
  According to the Korean Audiological Society, various factors such as an individual’s sensitivity to noise, size of noise, and duration of noise exposure are involved, but in general, NIHL can occur when the noise is more than 90 dB. The maximum sound intensity of general digital devices such as smartphones is 90 to 100 dB, so if people listen to music or watch videos for a long time at the maximum volume, the risk of hearing loss increases. It is known that the sound intensity of everyday conversation sounds is 50 to 60 dB, traffic noise in large cities is about 80 dB, and subway and motorcycle noise is about 80 to 90 dB. Therefore, when listening to music with digital devices and earbuds in noisy environments such as roads, buses, and subways, the risk of NIHL increases as the volume often reaches to 80 to 90 dB or more, which is the magnitude of the surrounding noise.
  In the case of NIHL, even if temporary hearing loss occurs after noise exposure, hearing usually recovers after a certain amount of rest time. However, if people are continuously exposed to noise for a long time without a break, it is difficult to recover their hearing at all, which is called Permanent Threshold Shift (PTS) or permanent hearing loss. Because once the hair cells, which transmit acoustic information to the brain, are damaged, they cannot be regenerated. In addition to temporary hearing loss, hearing loss is accompanied by various symptoms such as tinnitus, headache, dizziness, concentration loss, and memory loss. As such, hearing loss does not end in an uncomfortable problem in daily life. Thus, inspection and management of it are essential.
  To prevent NIHL, it is recommended to lower the volume as much as possible when wearing earbuds and refrain from using them for more than an hour. The World Health Organization (WHO) recommends that the maximum volume be within 60% when using earbuds and use them within an hour. If it is difficult to avoid noise exposure, it is also a way to reduce noise directly transmitted to the ear as much as possible. If the volume is often raised due to external noise, it is also a way to use noise-canceling earbuds to block noise. According to a survey, the volume can be reduced by up to 12 dB by using noise-cancelling earbuds. Also, it is recommended to refrain from using earbuds during exercise as much as possible. During an exercise, the temperature and humidity inside the ear increase due to heat and sweat, and earbuds prevent heat and sweat from being released. If you have sweat in your earphones, you need to dry them enough and keep them clean through regular disinfection.