HEARING HAZARD ASSOCIATED WITH INDUSTRIAL NOISE EXPOSURE

与工业噪声暴露相关的听力危害

• 批准号: 3420541
• 负责人: Roger P Hamernik
• 金额: $ 19.85万
• 依托单位: PLATTSBURGH STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-08-01 至 1998-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3420541
• 关键词: biological models; chinchilla; cochlea; environmental stressor; hearing disorders; histology; light microscopy; loudness; model design /development; noise biological effect; noise induced deafness; noise pollution; occupational hazard; vibration perception

Hearing loss in industrial workers accumulates from repeated daily (interrupted) exposures to excessive noise over a long period of employment. Most strategies designed to estimate hearing loss rely either upon extrapolations from experimental data acquired from short-term acute exposures or from noninterrupted long-term noise exposures or from epidemiological data with its typically 70 dB or more across-subject variability. Recent discoveries show that the peripheral auditory system can modulate the effects of noise exposure as much as 40 dB. These effects are believed to be partially mediated by the outer hair cell motor system which can be activated by a low-level noise exposure that precedes a hazardous noise exposure, or by interrupting a daily noise exposure regime. The outer hair cell bi-directional transduction system is also responsible for generating cochlear emissions which are now being intensively studied because of their potential use as a noninvasive and objective diagnostic test for noise-induced changes in outer hair cell function. Exposure to high-level impact noise continues to pose a problem to hearing in many industrial environments. Furthermore, there is virtually no experimental data on the accumulation of hearing loss from interrupted high-level impact noise and relatively little data available on the relation between cochlear emissions and noise-induced sensory cell pathology. Similarly, our knowledge of how low-level noise outside the work place affects hearing loss acquired in the work environment is very inadequate. The proposed research is designed to study the issues raised above in an animal model (chinchilla)by using as stimuli: (a) narrow band (400 Hz) impacts with center frequencies between 0.5 and 8.0 kHz to probe a wide frequency extent of the cochlea; (b) broad band impacts; and (c) complex high kurtosis continuous noise. The exposure paradigms will include both interrupted and noninterrupted exposures for 20 days and 5 days respectively. Exposures will be balanced for total energy so that comparisons based on energy can be made with existing data. Pure tone hearing threshold measured using evoked response audiometry and cubic distortion product evoked cochlear emission audiograms and input/output functions will be collected and correlated with sensory cell pathology. The objective is to contribute to: (l) an understanding of how hearing loss accumulates from repeated interrupted impact and complex noise exposures; (2) the development of the distortion product emission as an objective noninvasive diagnostic tool; and (3) an understanding and prediction of individual susceptibility to noise-induced hearing loss.

产业工人的听力损失因日常重复而累积 长期（中断）暴露在过多噪音中 就业。 大多数旨在估计听力损失的策略都依赖于 根据从短期急性期获得的实验数据推断 暴露或来自不间断的长期噪声暴露或来自 流行病学数据的跨主题通常为 70 dB 或更高 可变性。 最近的发现表明，外周听觉系统 可以调节高达 40 dB 的噪声暴露的影响。 这些 据信效果部分是由外毛细胞马达介导的 系统可以通过之前的低水平噪声暴露来激活 危险的噪音暴露，或中断日常噪音暴露 政权。 外毛细胞双向转导系统也是 负责产生耳蜗发射，目前正在研究 由于其作为非侵入性和非侵入性的潜在用途而受到深入研究 噪声引起的外毛细胞变化的客观诊断测试 功能。 暴露在高强度冲击噪音中仍然是一个问题 在许多工业环境中都能听到。此外，还有 实际上没有关于听力损失累积的实验数据 中断的高强度冲击噪音和相对较少的可用数据 耳蜗发射与噪声诱发的感觉细胞之间的关系 病理。同样，我们对外界低水平噪音的了解 工作地点对工作环境中获得的听力损失影响很大 不足。 拟议的研究旨在研究提出的问题 以上在动物模型（龙猫）中使用作为刺激：（a）窄带 (400 Hz) 影响，中心频率在 0.5 到 8.0 kHz 之间进行探测 耳蜗的频率范围很广； (b) 宽带影响；和（三） 复杂的高峰度连续噪声。 曝光范式将 包括 20 天和 5 天的间断和不间断暴露 分别为天。曝光量将根据总能量进行平衡，以便 可以与现有数据进行基于能量的比较。 纯音 使用诱发反应测听法和三次方测量听力阈值 失真产物引起的耳蜗发射听力图和输入/输出 将收集功能并与感觉细胞病理学相关。 目标是有助于： (l) 了解听力如何 损失因反复中断的冲击和复杂的噪音而累积 曝光； (2) 畸变产​​物发射作为 客观的无创诊断工具； (3) 理解和 预测个体对噪声引起的听力损失的易感性。