Karaoke can damage singers' voices and hearing

Researchers have confirmed what many people unlucky enough to listen to karaoke singing already knew—it can have adverse effects on health. Strenuous singing can damage the voice and increase the risk of noise induced hearing loss, according to two new studies. The popularity of karaoke singing, where the singer's voice is amplified against background accompanying music, has spread from Asia to Europe and North America, but few studies had looked at its impact on health. Researchers in Korea measured average and maximum sound pressure levels during performances of various types of karaoke singing, including ballads and rock. They also measured each singer's hearing threshold levels before and after 100 minutes of karaoke. Results showed that noise levels in the typical karaoke singing environment were higher than 95 decibels. Maximum noise levels frequently exceeded the US Occupational Safety and Health Administration's non-permissible level of 115 decibels, roughly equivalent to a pneumatic drill at a distance of one metre. "Further statistical analysis of hearing threshold shift revealed that up to 8dB of significant hearing loss was found at the most important human hearing frequency band, centred at 4000Hz, after about two hours of Karaoke noise exposure, indicating that Karaoke facilities may pose a serious threat to noise-induced hearing loss," warned the report of the study (International Journal of Industrial Ergonomics 2003;31:375-85). In a second study, researchers from Hong Kong University investigated the effects of karaoke singing on the voice (Journal of Voice 2003;17:216-27). Half of the singers taking part in the study were given water to drink and had short rests from singing at regular intervals, while the other half sang continuously without taking any water or rest. The results show that people who had drinks and rests not only sang for significantly longer than the other people but also sounded better. People who sang continuously without water or rest showed significant changes in their singing ability and were no longer able to hit the high notes after a time. "As most of the karaoke singers have no formal training in singing, these amateur singers are more vulnerable to developing voice problems under these intensive singing activities," the study concluded.