乙苯对职业人群神经行为的影响

The neurobehavioral effects of population occupationally exposed to ethylbenzene

目的评价乙苯对职业人群神经行为的影响。方法选择某石化公司苯乙烯合成原料车间246名乙苯上料工为接触组，相应的公司办公人员122名作为对照组，通过问卷调查，收集乙苯职业接触的基本信息。通过WHO神经行为核心测试组合（NCTB）法，测试对象的个体神经行为功能。结果接触组和对照组的4项消极情绪状态（紧张、抑郁、愤怒、困惑）得分之间差异无统计学意义（P〉0．05），接触组的积极情绪状态（有力）得分（16．29±8．61）明显低于对照组（18．46±9．52），疲劳得分（9．23±1．27）明显高于对照组（7．16±1．15），（P〈0．05）。接触组的平均反应时、数字广度得分明显高于对照组，手提转敏捷度、视觉记忆、目标追踪一Ⅱ正确打点数得分明显低于对照组，差异有统计学意义（P〈0．05）。按不同的工龄分段，接触组各工龄段间视觉记忆、目标追踪-Ⅱ正确打点数得分的差异无统计学意义（P〉0．05），3-、4～和5～年]-龄段的5项消极情绪状态（紧张、抑郁、愤怒、疲劳、困惑）得分及平均反应时得分均明显高于0～和2～年工龄段。3-、4一年工龄段的数字广度和3～、4～和5～年工龄段的手提转敏捷度、数字译码得分皆明显低于0～和2～年工龄段，差异均有统计学意义（P〈0．05）。结论乙苯可降低接触工人神经行为功能，工人神经行为功能在工龄为3年时发生了明显变化，工龄3年左右工人为乙苯神经行为损害的易感人群。

Objective To evaluate the influence of ethylbenzene on the neurobehavior of occupationally exposed workers. Methods The exposure group consisted of 246 workers occupationally exposed to ethylbenzene and 172 staffs from the offices served as controls. The basic information on ethylbenzene exposure was collected by the questionnaire. The nervous behavior and function of workers were evaluated by Neurobehavioral Core Test Battery （NCTB）. Results There were no differences of the scores for four emotional states （tension, depression, angry and bewilderment） between exposure group and control group （P〉0.05）. The score of emotion （vigor） in exposure group was significantly lower than that in control group （P〈0.05）, but the fatigue score in exposure group was significantly higher than that in control group （P〈0.05）. The score of mean reaction time in exposure group was significantly higher than that in control group （P〈 0.05）, the scores of digital span, manual dexterity, visual retention and target tracking in exposure group were significantly lower than those in control group （P〈0.05）. The exposure group was divided into 5 sub-groups, according to working duration. There were no differences for the scores of visual retention and target tracking among 5 sub-groups （P〉0.05）. The scores of five emotional states （tension, depression, angry, fatigue and bewilderment） in 3 sub-groups exposed to ethylbenzene for 3-, 4- and 5- years were significantly higher than those in 2 sub-groups exposed to ethylbenzene for 0- and 2- years （P〈0.05）. The scores of digital span in 2 sub-groups exposed to ethylbenzene for 3- or 4- years and the scores of manual dexterity and digital symbol in 3 sub-groups exposed to ethylbenzene for 3-, 4- and 5- years were significantly lower than those in 2 sub- groups exposed to ethylbenzene for 0- and 2 - years （P〈0.05）. Conclusion Ethylbenzene can depress the neurobehavioral functions of exposed workers. The neurobehavioral functions of workers exposed to ethylbenzene for 3 years changed significantly. The workers exposed to ethylbenzene for 3 year may be the susceptible population of neurobehavioral function impairment.