Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, Iowa 52242, USA.
J Occup Environ Hyg. 2012;9(3):129-39. doi: 10.1080/15459624.2011.652061.
Respirable dustiness represents the tendency of a powder to generate respirable airborne dust during handling and therefore indicates the propensity for a powder to become an inhalation hazard. The dustiness of 14 powders, including 10 different nanopowders, was evaluated with the use of a novel low-mass dustiness tester designed to minimize the use of the test powder. The aerosol created from 15-mg powder samples falling down a tube were measured with an aerodynamic particle sizer (APS). Particle counts integrated throughout the pulse of aerosol created by the falling powder were used to calculate a respirable dustiness mass fraction (D, mg/kg). An amorphous silicon dioxide nanopowder produced a respirable D of 121.4 mg/kg, which was significantly higher than all other powders (p < 0.001). Many nanopowders produced D values that were not significantly different from large-particle powders, such as Arizona Road Dust and bentonite clay. In general, fibrous nanopowders and powders with primary particles >100 nm are not as dusty as those containing granular, nano-sized primary particles. The method used here, incorporating an APS, represents a deviation from a standard method but resulted in dustiness values comparable to other standard methods.
可呼吸尘度表示粉末在处理过程中产生可呼吸性空气传播粉尘的趋势，因此表明粉末具有成为吸入危害的倾向。使用新型低质量尘度测试仪评估了包括 10 种不同纳米粉末在内的 14 种粉末的尘度，该测试仪旨在最大程度地减少测试粉末的使用。从粉末管中落下的 15 毫克粉末样品产生的气溶胶用空气动力学颗粒尺寸分析仪（APS）进行测量。通过测量粉末落下时形成的气溶胶的整个脉冲中的颗粒计数，计算出可呼吸尘度质量分数（D，mg/kg）。无定形二氧化硅纳米粉末的可呼吸 D 值为 121.4 mg/kg，明显高于所有其他粉末（p < 0.001）。许多纳米粉末的 D 值与大颗粒粉末（如亚利桑那州道路粉尘和膨润土粘土）没有显著差异。一般来说，纤维状纳米粉末和初级颗粒> 100nm 的粉末不如含有颗粒状、纳米级初级颗粒的粉末那么多尘。此处使用的方法，结合 APS，与标准方法有所偏离，但产生的尘度值与其他标准方法相当。
