Yamato H, Tanaka I, Higashi T, Kido M
Division of Respiratory Disease, University of Occupational and Environmental Health, Japan.
Br J Ind Med. 1992 Mar;49(3):182-5. doi: 10.1136/oem.49.3.182.
Deposition, clearance, retention, and durability of inhaled particles from lungs are known to be important factors for induction of pulmonary fibrosis or lung cancer. To study the deposition and clearance of alumina silicate ceramic fibres from the lung, male Wistar rats were exposed to ceramic fibre particles with a mass median aerodynamic diameter (MMAD) of 4.2 micron, for six hours a day, five days a week for two weeks. The average exposure concentration was 20.7 (standard deviation (SD) 4.5) mg/m3. The rats were killed at one day, three months, and six months after the end of exposure, and the fibre numbers and dimensions were measured with a scanning electron microscope. No significant differences in number and geometric mean length of residual ceramic fibres in the lungs were found between the groups. The geometric mean diameter, however, decreased according to the duration of the clearance period. These findings suggest that solubility of fibre contributes most in the clearance of the inhaled ceramic fibres from the lungs.
已知肺部吸入颗粒的沉积、清除、滞留和耐久性是诱发肺纤维化或肺癌的重要因素。为了研究硅酸铝陶瓷纤维在肺内的沉积和清除情况，将雄性Wistar大鼠暴露于质量中值空气动力学直径（MMAD）为4.2微米的陶瓷纤维颗粒中，每天暴露6小时，每周暴露5天，持续两周。平均暴露浓度为20.7（标准差（SD）4.5）mg/m³。在暴露结束后的1天、3个月和6个月处死大鼠，并用扫描电子显微镜测量纤维数量和尺寸。各组之间肺内残留陶瓷纤维的数量和几何平均长度没有显著差异。然而，几何平均直径根据清除期的持续时间而减小。这些发现表明，纤维的溶解度在从肺中清除吸入的陶瓷纤维方面起主要作用。
