Abdo K M, Graham D G, Timmons P R, Abou-Donia M B
J Toxicol Environ Health. 1982 Feb;9(2):199-215. doi: 10.1080/15287398209530155.
Neurotoxicity was produced in 1-yr-old hens (five hens per treatment) by continual 90-d exposure in inhalation chambers to atmospheres containing 50, 100, 200, or 400 ppm technical grade methyl butyl ketone (MBK) containing 70% methyl n-butyl ketone (MnBK) and 30% methyl isobutyl ketone (MiBK). A 30-d observation period followed. Severity of clinical condition and progression or improvement of neurological deficit signs were dependent on the concentration of MBK and duration of exposure. Hens exposed to the two highest levels developed ataxia and paralysis; they died or were sacrificed before the designated exposure period ended. The intermediate level of MBK (100 ppm) caused severe ataxia; most treated hens showed no change in clinical condition during the observation period. Hens exposed to 50 ppm exhibited gross ataxia, with most demonstrating partial regression of neurological deficit after the exposure ceased. Hens exposed to the lowest tested level (10 ppm) remained normal. Only hens exposed to 400 or 200 ppm showed significant weight loss. Some hens from the 50-400 ppm treatment groups showed unequivocal histopathologic changes in the spinal cord and peripheral nerves. Severity of histopathologic changes depended on the level and duration of MBK exposure. These changes were characterized by excessive swelling, phagocytosis, degeneration, and demyelination of the axons.
通过在吸入舱中持续90天暴露于含有50、100、200或400 ppm工业级甲基丁基酮（MBK）的大气中，对1岁母鸡（每组5只母鸡）产生神经毒性，该工业级甲基丁基酮含有70%的正丁基甲基酮（MnBK）和30%的异丁基甲基酮（MiBK）。随后有一个30天的观察期。临床状况的严重程度以及神经功能缺损体征的进展或改善取决于MBK的浓度和暴露持续时间。暴露于两个最高水平的母鸡出现共济失调和瘫痪；它们在指定的暴露期结束前死亡或被处死。MBK的中间水平（100 ppm）导致严重共济失调；大多数接受治疗的母鸡在观察期内临床状况没有变化。暴露于50 ppm的母鸡表现出明显的共济失调，大多数在暴露停止后神经功能缺损部分恢复。暴露于最低测试水平（10 ppm）的母鸡保持正常。只有暴露于400或200 ppm的母鸡出现显著体重减轻。50 - 400 ppm治疗组的一些母鸡在脊髓和周围神经中出现明确的组织病理学变化。组织病理学变化的严重程度取决于MBK暴露的水平和持续时间。这些变化的特征是轴突过度肿胀、吞噬作用、变性和脱髓鞘。
