Keppler Hannah, Dhooge Ingeborg, Maes Leen, D'haenens Wendy, Bockstael Annelies, Philips Birgit, Swinnen Freya, Vinck Bart
Ear, Nose, and Throat Department, Faculty of Medicine and Health Sciences, Ghent University, De Pintelaan 185, 9000 Ghent, Belgium.
Arch Otolaryngol Head Neck Surg. 2010 Jun;136(6):538-48. doi: 10.1001/archoto.2010.84.
To determine the output levels of a commercially available MPEG layer-3 (MP3) player and to evaluate changes in hearing after 1 hour of listening to the MP3 player.
First, A-weighted sound pressure levels (measured in decibels [dBA]) for 1 hour of pop-rock music on an MP3 player were measured on a head and torso simulator. Second, after participants listened to 1 hour of pop-rock music using an MP3 player, changes in hearing were evaluated with pure-tone audiometry, transient-evoked otoacoustic emissions, and distortion product otoacoustic emissions.
Twenty-one participants were exposed to pop-rock music in 6 different sessions using 2 types of headphones at multiple preset gain settings of the MP3 player.
Output levels of an MP3 player and temporary threshold and emission shifts after 1 hour of listening.
The output levels at the full gain setting were 97.36 dBA and 102.56 dBA for the supra-aural headphones and stock earbuds, respectively. In the noise exposure group, significant changes in hearing thresholds and transient-evoked otoacoustic emission amplitudes were found between preexposure and postexposure measurements. However, this pattern was not seen for distortion product otoacoustic emission amplitudes. Significant differences in the incidence of significant threshold or emission shifts were observed between almost every session of the noise exposure group compared with the control group.
Temporary changes in hearing sensitivity measured by audiometry and otoacoustic emissions indicate the potential harmful effects of listening to an MP3 player. Further research is needed to evaluate the long-term risk of cumulative noise exposure on the auditory system of adolescents and adults.
确定一款市售的MPEG-3（MP3）播放器的输出水平，并评估在使用该MP3播放器聆听1小时后听力的变化。
首先，在头和躯干模拟器上测量MP3播放器播放1小时流行摇滚音乐时的A加权声压级（以分贝[dBA]为单位）。其次，在参与者使用MP3播放器聆听1小时流行摇滚音乐后，通过纯音听力测定、瞬态诱发耳声发射和畸变产物耳声发射来评估听力变化。
21名参与者在6个不同的时间段内，使用两种类型的耳机，在MP3播放器的多个预设增益设置下接触流行摇滚音乐。
MP3播放器的输出水平以及聆听1小时后的临时阈值和发射变化。
对于头戴式耳机和随机附带的耳塞，在全增益设置下的输出水平分别为97.36 dBA和102.56 dBA。在噪声暴露组中，暴露前和暴露后测量之间发现听力阈值和瞬态诱发耳声发射幅度有显著变化。然而，畸变产物耳声发射幅度未出现这种模式。与对照组相比，噪声暴露组几乎每个时间段之间在显著阈值或发射变化的发生率上都观察到显著差异。
通过听力测定和耳声发射测量的听力敏感性的临时变化表明了聆听MP3播放器的潜在有害影响。需要进一步研究来评估青少年和成年人听觉系统累积噪声暴露的长期风险。
