The influence of whole-body vibration on noise-induced hearing loss: a review of animal experiments.
Hamernik-RP; Ahroon-WA; Davis-RI; Henderson-D
J Acoust Soc Am 1988 Mar; 83(Suppl 1):S21-S22
There is the suggestion in the literature that vibration may potentiate the effects of noise and may pose an increased risk of hearing loss. However, in human experimental studies, which, by necessity, are limited to low levels of TTS, the effects measured are consistent but relatively small. A very limited number of animal studies have also shown an enhanced hearing loss, but the scope of these studies is limited by a large intersubject variability and a small number of subjects. Also, the high levels of stimulation that were used in some of these animal experiments were not realistic. Our recent animal studies (chinchilla) have used a 30 Hz, 3-g-rms cage vibration in combination with continuous noise (95-dB, 0.5-kHz octave band) and impact noise (113-, 119-, or 125-dB peak SPL) exposure paradigms. All exposures lasted for 5 days. The impact noise exposures were designed to have an equal total energy. Temporary (compound) and permanent threshold shifts were measured using evoked potentials. Sensory cell populations were evaluated with the surface preparation technique. The results obtained from each of the above paradigms were consistent in showing that the presence of vibration did not have a statistically significant effect on hearing thresholds. A parallel set of experiments using a 20 Hz; 2-g-rms vibration is in progress. Preliminary conclusions are essentially the same as those of the 30-Hz experiments. The suitability of the chinchilla as an animalmodel for use in vibration experiments will also be discussed. [Work supported by NIOSH.]
Industrial-noise; Noise; Noise-exposure; Noise-frequencies; Environmental-exposure; Exposure-levels; Audiofrequency; Sound; Environmental-exposure; Environmental-hazards; Hazards; Sensory-thresholds; Models; Acoustics; Acoustic-signals; Animals; Laboratory-animals; Hearing-loss; Hearing; Vibration; Vibration-effects; Vibration-exposure; Cellular-function; Cellular-reactions; Cell-function
Journal of the Acoustical Society of America
Plattsburgh State University, New York