Rabinowitz P M, Galusha D, Dixon-Ernst C, Slade M D, Cullen M R
Yale University School of Medicine, Occupational and Environmental Medicine Program, New Haven, Connecticut 06510, USA.
Occup Environ Med. 2007 Jan;64(1):53-9. doi: 10.1136/oem.2005.025924. Epub 2006 Sep 14.
Much of what is known about the exposure-response relationship between occupational noise exposures and hearing loss comes from cross-sectional studies conducted before the widespread implementation of workplace hearing conservation programmes. Little is known about the current relationship of ambient noise exposure measurements to hearing loss risk.
To examine the relationship between rates of high frequency hearing loss and measured levels of noise exposure in a modern industrial workforce.
Ten-year hearing loss rates were determined for 6217 employees of an aluminium manufacturing company. Industrial hygiene and human resources records allowed for reconstruction of individual noise exposures. Hearing loss rates were compared to ANSI 3.44 predictions based on age and noise exposure. Associations between hearing loss, noise exposure, and covariate risk factors were assessed using multivariate regression.
Workers in higher ambient noise jobs tended to experience less high frequency hearing loss than co-workers exposed at lower noise levels. This trend was also seen in stratified analyses of white males and non-hunters. At higher noise exposure levels, the magnitude of hearing loss was less than predicted by ANSI 3.44 formulae. There was no indication that a healthy worker effect could explain these findings. The majority of 10 dB standard threshold shifts (STS) occurred in workers whose calculated ambient noise exposures were less than or equal to 85 dBA.
In this modern industrial cohort, hearing conservation efforts appear to be reducing hearing loss rates, especially at higher ambient noise levels. This could be related to differential use of hearing protection. The greatest burden of preventable occupational hearing loss was found in workers whose noise exposure averaged 85 dBA or less. To further reduce rates of occupational hearing loss, hearing conservation programmes may require innovative approaches targeting workers with noise exposures close to 85 dBA.
目前已知的职业噪声暴露与听力损失之间的暴露-反应关系，大多来自于在工作场所听力保护计划广泛实施之前进行的横断面研究。对于当前环境噪声暴露测量与听力损失风险之间的关系，我们了解甚少。
研究现代产业工人高频听力损失率与噪声暴露测量水平之间的关系。
确定了一家铝制造公司6217名员工的十年听力损失率。工业卫生和人力资源记录有助于重建个体噪声暴露情况。将听力损失率与基于年龄和噪声暴露的美国国家标准学会（ANSI）3.44预测值进行比较。使用多变量回归评估听力损失、噪声暴露和协变量风险因素之间的关联。
与在较低噪声水平下工作的同事相比，处于较高环境噪声工作岗位的工人往往高频听力损失较少。在白种男性和非狩猎者的分层分析中也观察到了这种趋势。在较高的噪声暴露水平下，听力损失的程度小于ANSI 3.44公式的预测值。没有迹象表明健康工人效应可以解释这些发现。大多数10分贝标准听阈偏移（STS）发生在计算得出的环境噪声暴露小于或等于85分贝A的工人中。
在这个现代产业队列中，听力保护措施似乎正在降低听力损失率，尤其是在较高的环境噪声水平下。这可能与听力保护的不同使用情况有关。可预防的职业性听力损失的最大负担出现在平均噪声暴露为85分贝A或更低的工人中。为了进一步降低职业性听力损失率，听力保护计划可能需要针对噪声暴露接近85分贝A的工人采取创新方法。
