Seppäläinen A M, Laine A, Salmi T, Riihimäki V, Verkkala E
Institute of Occupational Health, Helsinki, Finland.
Int Arch Occup Environ Health. 1989;61(7):443-9. doi: 10.1007/BF00386477.
Nine healthy male volunteers were exposed to m-xylene for 3 h in the morning and 40 min in the afternoon with a 40-min break in between. The atmospheric m-xylene concentrations were either stable at 8.2 mumol/l (200 ppm) or they fluctuated (5.2-16.4 mumol/l; 135-400 ppm) with peaks of 16.4 mumol/l and duration of 20 min at the beginning of each exposure session. The subjects were either sedentary or exercised at 100 W for 10 min at the beginning of each session during both exposure types. The two control days, with and without exercise, were similar to the exposure days but without exposure. Evoked potentials were recorded in the morning before the exposure and immediately after the morning and afternoon sessions. Visual evoked potentials were studied to a pattern reversal stimulus (pattern VEP) and to a light flash (flash VEP). For pattern VEPs the latencies of P50, N70, P100, N135 and P170 as well as the peak-to-peak amplitude of N70 to P100 were measured. For flash VEPs the latencies of P50, N70, P100, N150 and P200 as well as the peak-to-peak amplitude of P100 to N150 were measured. Short-latency auditory evoked potentials arising in the brainstem (BAEP) were recorded for a click stimulus. The peaks I, II, III, IV and V were identified from the grand averages. The effect of various exposure paradigms was evaluated by comparing the individual changes on an exposure day to those during the control days.(ABSTRACT TRUNCATED AT 250 WORDS)
九名健康男性志愿者于上午接触间二甲苯3小时，下午接触40分钟，中间休息40分钟。大气中间二甲苯浓度稳定在8.2微摩尔/升（200 ppm），或在每次接触时段开始时波动（5.2 - 16.4微摩尔/升；135 - 400 ppm），峰值为16.4微摩尔/升，持续20分钟。在两种接触类型的每个时段开始时，受试者要么久坐，要么以100瓦功率运动10分钟。两个对照日，一个有运动，一个无运动，与接触日相似，但无接触。在上午接触前、上午和下午接触时段结束后立即记录诱发电位。研究了对模式反转刺激（模式视觉诱发电位）和闪光（闪光视觉诱发电位）的视觉诱发电位。对于模式视觉诱发电位，测量P50、N70、P100、N135和P170的潜伏期以及N70至P100的峰峰值幅度。对于闪光视觉诱发电位，测量P50、N70、P100、N150和P200的潜伏期以及P100至N150的峰峰值幅度。记录了点击刺激引起的脑干短潜伏期听觉诱发电位（脑干听觉诱发电位）。从总体平均值中识别出I、II、III、IV和V峰。通过比较接触日与对照日个体变化来评估各种接触模式的影响。（摘要截选至250字）
