Hoet Perrine, Lison Dominique
Industrial Toxicology Unit, Faculty of Medicine, Université Catholique de Louvain, Brussels, Belgium.
Crit Rev Toxicol. 2008;38(2):127-70. doi: 10.1080/10408440701845443.
Noise is the most common preventable cause of irreversible sensorineural hearing loss. During recent years, the results of experimental and human investigations have raised the level of concern about the potential ototoxicity of chemical agents and their interaction with noise. European Directive 2003/10/EC on the minimum health and safety requirements regarding the exposure of workers to the risks arising from noise specifies that the employer shall give particular attention, when carrying out the risk assessment, to, among others, any effects on workers' health and safety resulting from interactions between noise and work-related ototoxic substances. There is, however, currently very little awareness in the occupational health community of the chemical hazards to hearing. The main objective of this review was to analyze the available scientific literature on the ototoxic effects of styrene and toluene, in order to examine dose-response/effect relationships and the relevance of the prevention strategy for people exposed to these solvents. While both solvents appear clearly ototoxic in rats, human data are less straightforward and the existing evidence does not allow characterization of the dose-response/effect relationships; further research is needed. However, once hearing loss is incurred, it is irreversible, and one should be alert to the possible hearing loss induced by toluene and styrene and to the possible additive, potentiating, or synergistic ototoxic effects in case of combined exposure to several chemicals and in case of combined exposure to noise and chemical substances.
噪声是不可逆性感音神经性听力损失最常见的可预防病因。近年来，实验研究和人体研究结果提高了人们对化学制剂潜在耳毒性及其与噪声相互作用的关注程度。欧洲关于工人暴露于噪声所产生风险的最低健康和安全要求的2003/10/EC号指令规定，雇主在进行风险评估时，除其他事项外，应特别关注噪声与工作相关耳毒性物质之间的相互作用对工人健康和安全产生的任何影响。然而，目前职业健康领域对听力化学危害的认识非常有限。本综述的主要目的是分析关于苯乙烯和甲苯耳毒性作用的现有科学文献，以研究剂量-反应/效应关系以及针对接触这些溶剂的人群的预防策略的相关性。虽然这两种溶剂在大鼠中均表现出明显的耳毒性，但人体数据则不那么直接，现有证据无法确定剂量-反应/效应关系；需要进一步研究。然而，一旦发生听力损失，就是不可逆的，人们应警惕甲苯和苯乙烯可能导致的听力损失，以及在接触多种化学物质以及接触噪声和化学物质合并存在的情况下可能出现的相加、增强或协同耳毒性作用。
