Loukzadeh Ziba, Shojaoddiny-Ardekani Ahmad, Mehrparvar Amir Houshang, Yazdi Zohreh, Mollasadeghi Abolfazl
Industrial Diseases Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
Department of Occupational Medicine, Qazvin University of Medical Sciences, Qazvin, Iran.
Iran J Otorhinolaryngol. 2014 Oct;26(77):235-43.
Hearing loss is one of the most common occupational diseases. In most workplaces, workers are exposed to noise and solvents simultaneously, so the potential risk of hearing loss due to solvents may be attributed to noise. In this study we aimed to assess the effect of exposure to mixed aromatic solvents on hearing in the absence of exposure to hazardous noise.
In a cross-sectional study, 99 workers from the petrochemical industry with exposure to a mixture of organic solvents whose noise exposure was lower than 85 dBA were compared with 100 un-exposed controls. After measuring sound pressure level and mean concentration of each solvent in the workplace, pure-tone-audiometry was performed and the two groups were compared in terms of high-frequency and low-frequency hearing loss. T-tests and Chi-square tests were used to compare the two groups.
The mean hearing threshold at all frequencies among petrochemical workers was normal (below 25 dB). We did not observe any significant association between solvent exposure and high-frequency or low-frequency hearing loss.
This study showed that temporary exposure (less than 4 years) to a mixture of organic solvents, without exposure to noise, does not affect workers' hearing threshold in audiometry tests.
听力损失是最常见的职业病之一。在大多数工作场所，工人同时暴露于噪声和溶剂中，因此溶剂导致听力损失的潜在风险可能归因于噪声。在本研究中，我们旨在评估在无有害噪声暴露的情况下，接触混合芳香族溶剂对听力的影响。
在一项横断面研究中，将99名来自石化行业、接触有机溶剂混合物且噪声暴露低于85分贝的工人与100名未接触的对照组进行比较。在测量工作场所每种溶剂的声压级和平均浓度后，进行纯音听力测试，并比较两组在高频和低频听力损失方面的情况。采用t检验和卡方检验对两组进行比较。
石化工人所有频率的平均听力阈值均正常（低于25分贝）。我们未观察到溶剂暴露与高频或低频听力损失之间存在任何显著关联。
本研究表明，在无噪声暴露的情况下，短期（少于4年）接触有机溶剂混合物不会影响工人在听力测试中的听力阈值。
