Korsak Z, Swiercz R, Rydzynski K
Department of Toxicity Evaluation, The Nofer Institute of Occupational Medicine, Lodz, Poland.
Int J Occup Med Environ Health. 1995;8(4):331-7.
Neurotoxic and sensory respiratory irritation effects of 1,2,4-trimethylbenzene (pseudocumene) in male rats and male Balb/C mice were investigated in condition of acute inhalation exposure. Rotarod performance and pain sensitivity behaviour were tested in rats exposed to pseudocumene at concentrations of 1230-9840 mg/m3 (250-2000 ppm) immediately after termination of a four-hour exposure. The respiratory rate was measured in mice by the whole body plethysmographic method in 6 min duration exposure to various concentrations of pseudocumene. Exposure to pseudocumene resulted in concentration-dependent disturbances in rotarod performance, decrease in pain sensitivity in rats and depression of respiratory rate in mice. The EC50 value for rotarod performance behaviour disturbances was 4693 mg/m3 (954 ppm) and for decrease pain sensitivity EC50 was 5682 mg/m3 (1155 ppm). The concentration depressing the respiratory rate to 50% (RD50) was 2843 mg/m3 (578 ppm). As based on RD50 value the MAC values for pseudocumene 85 mg/m3 (17.0 ppm) is suggested.
在急性吸入暴露条件下，研究了1,2,4-三甲基苯（均三甲苯）对雄性大鼠和雄性Balb/C小鼠的神经毒性和感觉性呼吸道刺激作用。在四小时暴露结束后，立即对暴露于浓度为1230 - 9840毫克/立方米（250 - 2000 ppm）均三甲苯的大鼠进行转棒试验和疼痛敏感性行为测试。通过全身体积描记法在暴露于不同浓度均三甲苯6分钟期间测量小鼠的呼吸频率。暴露于均三甲苯导致转棒试验性能出现浓度依赖性紊乱、大鼠疼痛敏感性降低以及小鼠呼吸频率抑制。转棒试验性能行为紊乱的半数效应浓度（EC50）值为4693毫克/立方米（954 ppm），疼痛敏感性降低的EC50为5682毫克/立方米（1155 ppm）。使呼吸频率降低50%的浓度（RD50）为2843毫克/立方米（578 ppm）。基于RD50值，建议均三甲苯的最大允许浓度（MAC）值为85毫克/立方米（17.0 ppm）。
