Evaluation of physical/chemical synergistic influence of the working environmental factor on hearing, and the application to the comfortable environment.

工作环境因素对听力的物理/化学协同影响评价及其在舒适环境中的应用。

基本信息

批准号：
11670384
负责人：
MIYASHITA Kazuhisa
金额：
$ 2.43万
依托单位：
Wakayama Medical University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2001
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11670384/
关键词：
Hearing Auditory Brainstem Response (ABR)Noise Organic Solvents Combined effect Synergistic effect 相乗影響

项目摘要

To clarify of evaluation of physical/chemical synergistic influence of the working environmental factor on hearing, and the application to the comfortable environment, animal experiments were carried out, and the male workers were examined.The subjects were male guinea pigs. Hearing threshold was measured by auditory brainstem response. The first experiment was only for methanol exposure, and methanol inhalation levels were 500 ppm, 900 ppm, 1500 ppm, 1900 ppm, 2400 ppm and 3000 ppm. The results of the first experiment demonstrated that methanol inhalation more than 1900ppm dose-dependently increased the hearing threshold. The second experiment was only for noise exposure, and noise exposure levels were 90, 100 and 105 dB SPL. The detection threshold in the 105 dB group was significantly increased. In the third experiment, guinea pigs were exposed to 1500 ppm or 1900 ppm methanol as sub-ototoxic concentration following 100 dB SPL white noise as sub-ototoxic level. In the combined group … More , the marked increase in the detection threshold was observed. The increase detection threshold was the greatest in the group of 1900 ppm methanol combined with noise.We measured hearing level and upper limit of hearing in 93 male workers occupationally exposed to organic solvents and noise. Environmental monitoring, biological monitoring and noise level measurement in workplaces were done. Most exposure level of organic solvents and/or noise were within the occupational exposure limits. The prevalence rate of upper limit of hearing below 75th percentile curve was higher in workers exposed to organic solvents and noise, and the upper limit of hearing was reduced in workers who were exposed for 5 years or more. This reduction was dose-dependent and was related to styrene concentrations in breathing-zone air and mandelic acid concentrations in urine. The results suggest that the probable synergistic effect of organic solvents and noise on hearing should be considered even when the exposures are within the occupational exposure limits. Less

为了阐明工作环境因素对听力的物理/化学协同影响，并对舒适的环境进行了应用，进行了动物实验，并检查了男性工人。受试者是雄性豚鼠。听力阈值是通过听觉脑干响应来衡量的。第一个实验仅是用于甲醇暴露的，甲基戊醇事故水平为500 ppm，900 ppm，1500 ppm，1900 ppm，2400 ppm和3000 ppm。第一个实验的结果表明，甲基吸入超过1900 ppm的剂量依赖性地增加了听力阈值。第二个实验仅用于噪声暴露，噪声暴露水平为90、100和105 dB SPL。 105 dB组的检测阈值显着增加。在第三次实验中，在100 dB Spl白噪声作为亚毒素水平后，将豚鼠暴露于1500 ppm或1900 ppm甲醇作为亚毒素浓度。在组合组中……更多，观察到检测阈值的明显增加。增加检测阈值是1900 ppm甲基醇与噪声结合的组中最大的。我们测量了听力水平和听力上限，93名男性工人占据了有机溶液和噪声。在工作场所进行了环境监测，生物监测和噪声水平测量。大多数有机解决方案和/或噪声的暴露水平都在职业暴露范围内。在暴露于有机解决方案和噪声的工人中，听力高于第75个百分位数曲线的上限的患病率较高，并且在暴露5年或更长时间的工人中，听力的上限降低了。这种降低是依赖剂量的，与尿液中呼吸区空气和曼德尔酸浓度的苯乙烯浓度有关。结果表明，即使暴露在职业暴露极限范围内，也应考虑有机溶液和噪声对听力的可能协同作用。较少的