Francovitch R J, Deal D L, Tayyeb M I, Wolpert R L, Boger J R, Valentini J E, Menzel D B
Toxicol Lett. 1987 Sep;38(1-2):19-32. doi: 10.1016/0378-4274(87)90107-x.
We have designed a low-cost, compact, head-only exposure system which is easy to use and allows exposure of up to 8 or 16 small rodents depending on the chamber used with the system. Animals are exposed without anesthesia or extreme restraint. Deflection tubes at the chamber inlet and outlet serve to provide turbulent flow within the chamber. Performance of the exposure system was evaluated by analyzing data which was collected during investigations of the kinetics of respirable nickel chloride (NiCl2) and cobalt chloride (CoCl2) aerosols in Sprague-Dawley rats. Acute 2 h exposure to NiCl2 at concentrations ranging from 129 to 1208 micrograms Ni/m3 (MMAD 0.7-0.9 micron, sigma g 1.2-1.5) had a mean run-to-run coefficient of variation (cv) in chamber concentration of 11.6%, and a mean within-run cv of 8.5%. A 26-day repeated exposure of 3 groups of rats to 18.4 micrograms Ni/m3 gave a mean run-to-run cv of 20.9%, mean within-run cv of 10.2%, and within-day cv of 14.5%. Acute exposure studies with CoCl2 at concentrations ranging from 298 to 1371 micrograms Co/m3 (MMAD 0.9, sigma g 1.4) produced a mean run-to-run cv of 8.4% and a mean within-run cv of 7.8%. The repeated exposure of 2 groups of rats for 5 days to CoCl2 at a concentration of 583 micrograms Co/m3 had a mean run-to-run cv of 10.1%, a within-run cv of 7.4% and a within-day cv of 6.8%. The distribution of aerosol within the chamber is shown to have been uniform, and chamber performance was linear over the range tested. This system provides an inexpensive and uniform means of conducting inhalation exposure studies with selected airborne contaminants that might represent a potential health hazard.
我们设计了一种低成本、紧凑的仅头部暴露系统，该系统易于使用，根据与系统配套使用的舱室不同，可对多达8只或16只小型啮齿动物进行暴露。动物在无麻醉或极少约束的情况下接受暴露。舱室入口和出口处的导流管用于在舱室内提供湍流。通过分析在对Sprague-Dawley大鼠可吸入氯化镍（NiCl2）和氯化钴（CoCl2）气溶胶动力学进行研究期间收集的数据，对暴露系统的性能进行了评估。在浓度范围为129至1208微克镍/立方米（质量中值空气动力学直径0.7 - 0.9微米，几何标准差1.2 - 1.5）的条件下对NiCl2进行2小时急性暴露，舱室内浓度的平均批间变异系数（cv）为11.6%，批内平均cv为8.5%。3组大鼠在26天内重复暴露于18.4微克镍/立方米的环境中，批间平均cv为20.9%，批内平均cv为10.2%，日内cv为14.5%。在浓度范围为298至1371微克钴/立方米（质量中值空气动力学直径0.9，几何标准差1.4）的条件下对CoCl2进行急性暴露研究，批间平均cv为8.4%，批内平均cv为7.8%。2组大鼠在5天内重复暴露于浓度为583微克钴/立方米的CoCl2环境中，批间平均cv为10.1%，批内cv为7.4%，日内cv为6.8%。结果表明，气溶胶在舱室内的分布是均匀的，并且在测试范围内舱室性能呈线性。该系统为使用可能代表潜在健康危害的特定空气传播污染物进行吸入暴露研究提供了一种廉价且均匀的方法。
