Takahashi H, Yoshida M, Murao N, Maita K
Institute of Environmental Toxicology, Ibaraki, Japan.
Toxicol Lett. 1994 Aug;73(2):103-11. doi: 10.1016/0378-4274(94)90100-7.
This study was designed to evaluate that a difference in the route of absorption or the mode of lethality is responsible for the higher inhalation lethality of micron-sized organophosphorus insecticide, chlorfenvinphos (CVP), aerosols than the submicron-sized aerosols. Male Fischer 344 rats were exposed to the micron-sized (> 1 micron) or the submicron-sized aerosols (< 1 micron) for 4 h using the nose-only exposure system. LC50 of the micron-sized and the submicron-sized aerosols was 0.13 mg/l and 0.51 mg/l, respectively. Placing a drain cannula in the esophagus markedly increased LC50 of the micron-sized aerosols to 0.49 mg/l, but not that of the submicron-sized aerosols. There was no qualitative difference in lethal profile in cardiorespiration between 2 types of aerosols. The higher lethality of the micron-sized aerosols could be ascribed to swallowed CVP.
本研究旨在评估微米级有机磷杀虫剂毒虫畏（CVP）气雾剂比亚微米级气雾剂具有更高吸入致死率的原因是吸收途径的差异还是致死方式的不同。使用仅经鼻暴露系统，将雄性Fischer 344大鼠暴露于微米级（>1微米）或亚微米级气雾剂（<1微米）中4小时。微米级和亚微米级气雾剂的半数致死浓度（LC50）分别为0.13毫克/升和0.51毫克/升。在食管中放置引流插管可使微米级气雾剂的LC50显著增加至0.49毫克/升，但对亚微米级气雾剂则无此作用。两种气雾剂在心肺呼吸致死特征上没有质的差异。微米级气雾剂较高的致死率可归因于吞咽的CVP。
