Synergistic Ototraumatic Effects of Toluene Exposure in Hazardous Noise Environments
Capt Cynthia A. Sabin, USAF, BSC – Fairchild AFB, WA
LtCol John R. Allen, USAF – Andrews AFB, MD
Mr. William Jackson, Brooks AFB, TX
Hazardous noise exposure in military and industrial environments causes hearing loss in employees who are not adequately protected. Similarly, workers exposed to various neurotoxic, industrial chemicals, such as toluene, have been found to exhibit a variety of auditory deficits. Recent literature suggests that there may be a synergistic effect between hazardous noise and toluene; combined exposures appeared to accelerate and exacerbate hearing loss. The purpose of this study was to determine whether there was any increased risk of loss for workers exposed to both noise and toluene as compared with workers exposed to noise alone. A retrospective cohort study was employed. Subjects consisted of male and female workers at Kelly AFB, of which 1,011 were exposed to both agents, and 396 were exposed only to noise. Results failed to demonstrate a synergistic effect of noise and toluene. Further, there was no apparent effect of noise alone or toluene alone. Additionally, what had, on preliminary review of the data, appeared to be a dose- response relationship, did not hold up under further analysis. However, age and gender were significant (p<.001) factors, where older individuals had greater hearing loss than younger persons, and men had more hearing loss than women. Results suggest one or more of the following: 1) Kelly workers are better protected than those in other studies; 2) exposure levels are lower than those of other studies; 3) the period monitored was not sufficient to show a change in hearing; 4) confounding factors obscured any change. The authors discuss the implications of these results and make recommendations for further studies.
Air Force Audit Agency Findings: Implications for HCPs
LtCol Craig Jordan, USAF, BSC
Brooks AFB, TX
The Air Force Audit Agency recently conducted an audit of the hearing conservation programs (HCPs) at 10 Reserve and Guard bases. The findings and common problems identified by the audit will be presented. Suggestions for improvements to the AF HCP will be discussed. A portion of the briefing will be set aside for group discussion of the issues presented.
Auditory Readiness Information Center
Capt John Hall, USAF, BSC
Lakenheath RAF, UK
As commonly known, noise-induced hearing loss is one of the two largest occupational illnesses in the Air Force. As with any preventable disease, education and intervention are the keys to minimization of the epidemic. Air Fete ’98 provided this audiologist with the perfect platform to launch the Auditory Readiness Information Center (ARIC) to educate military (and civilian) visitors on preventive hearing conservation topics. This presentation will discuss the efforts required to get the ARIC approved for Air Fete ’98 and the outcome of such an endeavor.
Innovative Protocol for Trans-Cranial Cross Hearing Aids: Case Studies
Capt Cynthia Sabin, USAF, BSC
Fairchild AFB, WA
Introduction of the deep fitting Tympanette hearing aid has opened a door for the unilateral hearing loss patient. No longer is a CROS or BICROS hearing aid the only choice for obtaining sense of direction of sound and improved ability to understand in background noise. Historically, success of fitting a unilateral loss with trans-cranial crossover has been less than 50%. A protocol was developed at Fairchild AFB to serve as a guideline for fitting these individuals. Use of the FAFB protocol has succeeded in 100% success (3 of 3). The protocol will be discussed and individual case studies will be presented.
Epidemiology and Applications in Audiology
1Lt Kathy Niewijk, USAF, BSC
Chief, Public Health
Kunsan AB, Korea
There are many ways to approach problem solving and research in audiology. Epidemiology is a science that systematically identifies causal and preventable factors of human disease and injury. This session will describe the basic elements of epidemiology as the study of the distribution and determinants of health related states or events in specified populations, and the application of this sort of study to the field of audiology. The organization of biostatistical data and the use of various methods of analytic study design to explore the relationship of hearing loss and ballistics, ototoxic organic solvents, vibration, pharmaceuticals, and noise will be discussed. In addition, the use of epidemiologic principles to evaluate the effectiveness of hearing conservation programs and other training and motivational aspects of hearing loss prevention efforts will be reviewed.