Foy Jeffrey W-D, Collier Clare, Swauger James E
Scientific and Regulatory Affairs, R J Reynolds Tobacco Company, Winston-Salem, NC 27102-1487, USA.
Inhal Toxicol. 2003 Feb;15(2):167-79. doi: 10.1080/08958370304473.
Biopersistence plays a significant role in determining the potential bioactivity of respirable fibers. In vivo biopersistence in the lung is frequently assessed by in vitro fiber dissolution studies using simulated biological solutions and flow-through techniques. The dissolution rate (k) of a fiber is typically determined by elemental analysis of the flow-through solution to measure the mass of material leached from the fibers over a given time. Various methods may be used to estimate the value of k from these results. The present study compared the in vitro dissolution characteristics of seven experimental glass fiber compositions to those obtained for four recognized fiber compositions (MMVF 10-glass fiber; MMVF 11-glass fiber; MMVF 21-rockwool fiber; crocidolite fiber). Fiber dissolution was examined over a 17-wk period using a flow-through system designed to simulate the conditions encountered by fibers in the extracellular environment of the lung. Mass loss and changes in fiber diameter were determined over time and were then used to calculate k using five different methods. Although the selected methodologies did not produce identical estimations of k for each fiber, the resulting ranking of fiber solubility for each method was consistent. The seven experimental glass fibers were found to have k values intermediate between those of MMVF 11 and MMVF 21.
生物持久性在决定可吸入纤维的潜在生物活性方面起着重要作用。肺部的体内生物持久性通常通过使用模拟生物溶液和流通技术的体外纤维溶解研究来评估。纤维的溶解速率（k）通常通过对流通溶液进行元素分析来确定，以测量在给定时间内从纤维中沥出的物质质量。可以使用各种方法从这些结果中估计k值。本研究将七种实验性玻璃纤维组合物的体外溶解特性与四种公认的纤维组合物（MMVF 10 - 玻璃纤维；MMVF 11 - 玻璃纤维；MMVF 21 - 岩棉纤维；青石棉纤维）的体外溶解特性进行了比较。使用一个旨在模拟纤维在肺部细胞外环境中所遇到条件的流通系统，在17周的时间内对纤维溶解进行了研究。随着时间的推移测定质量损失和纤维直径的变化，然后使用五种不同方法计算k值。尽管所选方法对每种纤维的k值估计并不相同，但每种方法所得出的纤维溶解度排名是一致的。发现七种实验性玻璃纤维的k值介于MMVF 11和MMVF 21的k值之间。
