MODELS FOR ASSESSING RISK OF OCCUPATIONAL HEARING LOSS

描述：（改编自研究者摘要）拟议工作 将确定促进增强的暴露条件， 化学窒息剂碳引起的噪声性听力损失 一氧化物和氰化物。 很有可能这些因素结合在一起 暴露于噪音会比单独的噪音产生更大的听力损失风险， 基于阳性实验室动物的人体允许暴露水平 数据，并初步了解化学品 窒息物会干扰听力 老鼠会暴露在各种噪音中 单独或噪声与一氧化碳和氰化物的组合，以评估 听觉功能的暂时性和永久性损伤。 的 这项研究的主要目的是防止人类听力损失 通过确定促进协同作用的暴露条件， 相互作用化学窒息剂，如氰化物和一氧化碳， 噪声 研究人员将确定暴露与 持续时间、化学窒息物浓度和噪声强度 促进协同（大于加和）相互作用，如由 耳蜗功能损害和组织病理学研究。 调查人员还将确定噪音与 频谱和与化学窒息剂的相互作用， 准确的预测可以应用于工作场所设置， 可能存在有限的噪声。

DESCRIPTION: (Adapted from the Investigator's Abstract) The proposed work would identify the exposure conditions that facilitate the potentiation of noise induced hearing loss (NIHL) by the chemical asphyxiants carbon monoxide and cyanide. A strong likelihood exists that these combined exposures produce greater risk of hearing loss than noise alone at permissible exposure levels in humans, based upon positive laboratory animal data, and a preliminary understanding of the mechanisms by which chemical asphyxiants disrupt hearing. Rats will be exposed to various types of noise alone or to noise in combination with carbon monoxide and cyanide to assess both temporary and permanent impairments of auditory function. The principal objective of this investigation is to prevent human hearing loss by determining the exposure conditions that facilitate a synergistic interaction chemical asphyxiants such as cyanide and carbon monoxide and noise. The investigators will determine the relationship between exposure duration, concentration of chemical asphyxiants and noise intensity in promoting a synergistic (greater than additive) interaction as indexed by functional impairment of the cochlea and histopathological investigation. The investigators will also determine the relationship between the noise frequency spectrum and interactions with chemical asphyxiants so that accurate predictions can be applied to work place settings where band limited noise may be present.