Bellmann B, Muhle H, Kamstrup O, Draeger U F
Fraunhofer Inst. Toxicol, Aerosol Res. Hannover, Germany.
Exp Toxicol Pathol. 1995 May;47(2-3):195-201. doi: 10.1016/S0940-2993(11)80314-3.
The biodurability is one of the essential factors for a carcinogenic potential of mineral fibres. The in vivo solubility of commercial fibre products can be influenced by modifications of the chemical composition. Two types of experimental stone wool samples with new chemical composition were compared to a commercial stone wool sample. Sized fractions of these samples with median lengths of 7.1, 9.3 and 6.7 microns, respectively, and median diameters of 0.76, 1.02 and 0.63 microns, respectively, were intratracheally instilled into female Wistar rats with a single dose of 2 mg in 0.3 ml. 5 animals per group were sacrificed after 2 days, 1, 3, 6, 12 and 18 months. After low-temperature ashing of the lungs about 1,000 fibres per group and sacrifice date were analysed in SEM for length and diameter. The number of fibres in the total lung was calculated. An analysis of fibre number of different length and diameter fractions was used to estimate whether dissolution, breakage or mechanical clearance is responsible for the elimination of fibres from the lung. Results indicate that the breakage of fibres with length above 20 microns and the dissolution of fibres was faster in the experimental stone wool samples compared to the commercial sample.
生物耐久性是矿物纤维致癌潜力的重要因素之一。商业纤维产品的体内溶解度会受到化学成分改变的影响。将两种具有新化学成分的实验性岩棉样品与一种商业岩棉样品进行了比较。分别将这些样品的粒度级分气管内注入雌性Wistar大鼠，中位长度分别为7.1、9.3和6.7微米，中位直径分别为0.76、1.02和0.63微米，单剂量为2毫克，溶于0.3毫升。每组5只动物在2天、1、3、6、12和18个月后处死。肺经低温灰化后，每组约1000根纤维，按处死日期在扫描电子显微镜下分析其长度和直径。计算肺内纤维总数。通过分析不同长度和直径级分的纤维数量来估计是溶解、断裂还是机械清除导致纤维从肺中消除。结果表明，与商业样品相比，实验性岩棉样品中长度超过20微米的纤维断裂和纤维溶解更快。
