Hesterberg T W, McConnell E E, Miller W C, Hamilton R, Bunn W B
Health, Safety and Environment Department, Mountain Technical Center, Schuller International, Littleton, Colorado 80162-5005.
Fundam Appl Toxicol. 1992 Oct;19(3):358-66. doi: 10.1016/0272-0590(92)90174-g.
This study was initiated to assess the pulmonary toxicity of a polyolefin fiber composed of polypropylene in male Fischer 344 rats after 90 days of inhalation exposure. To increase fiber respirability in the rodent, polypropylene fibers were size-selected before aerosolization to have a geometric mean diameter of 1.6 microns (46% < 1 micron) and a geometric mean length of 30.3 microns. Three groups of animals were exposed in nose-only inhalation chambers, 6 hr/day, 5 days/week, for 90 days to 15, 30, or 60 mg/m3 of polypropylene, or filtered air (negative control). Microscopic examination of the polypropylene fiber-exposed lungs revealed that, at all time points examined in the study, there was a dose-dependent increase in pulmonary macrophages. These minimal or mild increases in cellularity appeared to be reversible, especially at the lower doses 30 days post exposure. No fibrosis was observed in any of the groups. A strong correlation was found between the external exposure concentration, the time of exposure, and the lung fiber burden. The number of partially degraded (segmented) fibers within the lung increased with the exposure concentration and period of exposure, as well as with the period of recovery after termination of exposure at 90 days. Fibers were recovered from exposed lungs using a hypochlorite digestion technique.
本研究旨在评估雄性Fischer 344大鼠吸入暴露90天后，由聚丙烯组成的聚烯烃纤维的肺毒性。为了提高纤维在啮齿动物中的可吸入性，在雾化前对聚丙烯纤维进行了尺寸筛选，使其几何平均直径为1.6微米（46%<1微米），几何平均长度为30.3微米。三组动物在仅鼻吸入舱中暴露，每天6小时，每周5天，持续90天，暴露于15、30或60毫克/立方米的聚丙烯或过滤空气（阴性对照）中。对暴露于聚丙烯纤维的肺部进行显微镜检查发现，在研究中检查的所有时间点，肺巨噬细胞均呈剂量依赖性增加。这些细胞数量的最小或轻度增加似乎是可逆的，尤其是在暴露后30天的较低剂量下。在任何组中均未观察到纤维化。在外部暴露浓度、暴露时间和肺纤维负荷之间发现了很强的相关性。肺内部分降解（分段）纤维的数量随着暴露浓度、暴露时间以及90天暴露终止后的恢复时间而增加。使用次氯酸盐消化技术从暴露的肺部回收纤维。
