Presenting the study at the American Academy of Otolaryngology-Head and Neck Surgery Foundation's Annual Meeting & OTO EXPO in Washington, DC, the researchers said that 100 people who had used cellular phones for over a year suffered increases in the degree of hearing loss over the span of 12 months.
The researchers have also found that people who used their phones for more than 60 minutes a day had a worse hearing threshold than their counterparts with lesser use.
High frequency hearing loss is characterized by the loss of ability to hear consonants such as s, f, t, and z, even though vowels can be heard normally. As a result of high frequency hearing loss, people hear sounds but fail to make out what is being said.
Symptoms such as ear warmth, ear fullness, and ringing in the ears (tinnitus) are the early warning signs of an auditory abnormality, say authors of the study.
The authors also said that the use of earphones was safer than holding a mobile phone up to the ears.