Laine A, Savolainen K, Riihimäki V, Matikainen E, Salmi T, Juntunen J
Social Insurance Institution, Helsinki, Finland.
Int Arch Occup Environ Health. 1993;65(3):179-88. doi: 10.1007/BF00381154.
Nine male volunteers were exposed to either a constant or a fluctuating exposure pattern of m-xylene with a time-weighted average exposure concentration of 200 ppm in both cases. The subjects remained sedentary throughout the exposure, or the exercised at 100 W for 10 min at the beginning of the morning and the afternoon sessions. In another experiment, 12 sedentary male volunteers were exposed to a fixed 200 ppm of m-xylene. The effects of m-xylene on body sway, reaction time performance, and overnight sleep were measured. Body balance was stabilized after exposure to the peaks of 400 ppm of m-xylene in both sedentary and exercising subjects. Simple visual reaction times were prolonged after the peak exposures at rest whereas auditive choice reaction times were prolonged after peaks combined with exercise. Exposure to m-xylene at a constant level of 200 ppm did not affect the ratio of "active" to "quiet" sleep in the volunteers as measured with the static charge sensitive bed recording, but decreased slightly the number of body movements in bed. On the next morning no changes were found in body sway and reaction time performance as compared to the morning before exposure.
九名男性志愿者分别暴露于间二甲苯的恒定或波动暴露模式下，两种情况下的时间加权平均暴露浓度均为200 ppm。在整个暴露过程中，受试者保持久坐状态，或者在上午和下午的实验开始时以100瓦的功率运动10分钟。在另一项实验中，12名久坐的男性志愿者暴露于固定的200 ppm间二甲苯中。测量了间二甲苯对身体摇摆、反应时间表现和夜间睡眠的影响。在久坐和运动的受试者中，暴露于400 ppm间二甲苯峰值后，身体平衡得以稳定。休息时峰值暴露后简单视觉反应时间延长，而峰值与运动相结合后听觉选择反应时间延长。以200 ppm的恒定水平暴露于间二甲苯对志愿者通过静电荷敏感床记录测量的“活跃”睡眠与“安静”睡眠的比例没有影响，但在床上的身体运动次数略有减少。与暴露前的早晨相比，第二天早晨身体摇摆和反应时间表现没有变化。
