Using a mobile phone regularly could increase the risk of tinnitus, a condition which causes noise in the ears such as a ringing, roaring or hissing, experts say.
About 10 to 15 per cent of adults have chronic tinnitus and it affects quality of life, such as preventing sleeping, in up to 3 per cent of sufferers.
Austrian scientists studied 100 people with the condition; 27 had tinnitus in their right ear, 38 in the left and 35 in both ears. Those who used a mobile phone on one ear for four years or more were almost twice as likely to develop tinnitus in that ear.
The research was published online in the Journal of Occupational and Environmental Medicine.