Source: Williams, Warwick PhD
The Hearing Journal, Volume 68, Issue 12, pp 28, 30
The possibility of leisure activities—especially listening to music on portable music players—causing hearing loss in young people never fails to excite the press. The many stories on this topic seem to reflect genuine concern in the population about this issue.
As this article by Warwick Williams, PhD, shows, however, this concern does not seem well founded for nearly all young people. This is not to say that leisure noise cannot cause hearing loss, but it certainly does not seem to be very common.
There are two caveats: First, recent analysis of the extensive data discussed by Dr. Williams has shown a significant relationship between total leisure-induced noise exposure and the occurrence of tinnitus, so it seems that noise exposure is indeed having some effects on the ears of some young people, even if it is not reflected in their hearing thresholds. These effects seem to occur even with accumulated noise doses much lower than those that would occur in a workplace with average daily levels of 85 dBA.
Second, the study that Dr. Warwick describes was carried out before we realized the importance of looking for the symptoms of “hidden hearing loss”—the loss of high-threshold nerve fibers that have no effect on hearing thresholds but probably contribute to the accurate analysis of sound at moderate or high noise levels. A new, large-scale study is now under way to explicitly look for these symptoms, one of which may well be an increased prevalence of tinnitus.
Although the study was done on an Australian population, ears are the same everywhere, and the types of devices that people use for music are international, so it seems likely that the results would apply to other populations. If so, then the safety message we have so far for other countries is that the most dangerous leisure noise activities seem to be dance parties.
For just a very small proportion of young people, the combination of high sound levels and exposures of several hours per outing repeated weekly for several years is certainly sufficient to provide noise exposure sufficient to damage hearing, even if the number who receive this much exposure is small.
—Harvey Dillon, PhD
National Acoustic Laboratories
See full article here.