A common enough syndrome, especially as hearing loss usually develops over a period of several years. As a result, the decline is usually painless and gradual, and thus, many people may not notice the imperceptible deterioration in hearing quality.
Invariably, the first recognition of a hearing problem may be difficulty in understanding what is being said because of no longer being able to distinguish words clearly. This is more than likely to occur when one is trying to hear in a noisy place such as in a crowd or at a party. Another example could be the frequent turning up of the volume on TV or radio. These symptoms could be the beginning of high-frequency hearing loss.
A more definitive awareness of possible hearing damage is the effects of tinnitus, which is a ringing or another type of sound experienced in the ear. The onset of tinnitus could be the result of long-term exposure to excessive noise levels in the workplace which has damaged the hearing nerve, which could lead to long term industrial deafness.
An individual suffering noise induced hearing loss will initially show only a high frequency loss at 4000 Hz. – a measure of sound frequency or pitch – when taking an audiogram or hearing test. With continued noise exposure and hearing loss, the audiogram will show a broader loss to include lower (deeper) frequencies.
Noise-induced hearing loss will almost always affect both ears equally, but in some situations, especially when using firearms, the ear opposite the side of the trigger finger is likely to be seriously affected.
While there is no cure for hearing damage caused by noise-induced hearing loss, recent animal research into the use of antioxidants to both prevent hearing loss and restore hearing are looking at vitamins A, C, E and magnesium taken prior to loud noise exposure to prevent hearing loss. Studies on humans are also in progress.