McIntyre Powder (MP) is a finely ground aluminum powder that was used between 1943 and 1979 as a prophylaxis for silicosis. Silicosis is a chronic lung disease caused by the inhalation of crystalline silica dust and was prevalent in the Canadian mining industry during this time period. The McIntyre Research Foundation developed, patented, and produced the MP and distributed it to licensees in Canada, the United States, Mexico, Chile, Belgian Congo, and Western Australia. In the province of Ontario, Canada it is estimated that at least 27,500 miners between 1943 and 1979 were exposed to MP. The present study was undertaken to examine the chemical and physical characteristics of two variations of MP (light grey and black). Chemical analyses (using X-ray Fluorescence and Inductively Coupled Plasma approaches) indicate that the black MP contains significantly higher concentrations of aluminum and metal impurities than the light grey MP (p < 0.001). X-ray diffractometry shows that while aluminum hydroxide dominates the aluminum speciation in both variations, the higher total aluminum content in the black MP is attributable to a greater proportion of elemental aluminum. Physical characterization (using electron microscopy, light microscopy, and dynamic light scattering) indicates that the light grey MP consists of particles ranging from 5 nm to 5 µm in diameter. Atomic Force Microscopy shows that the light grey MP particles in the nanoparticle range (<100 nm) have a mode between 5 and 10 nm. Consequently, it is possible that inhaled smaller MP nanoparticles may be transported via blood and lymph fluid circulation to many different organs including the brain. It is also possible for inhaled larger MP particles to deposit onto lung tissue and for potential health effects to arise from inflammatory responses through immune activation. This MP characterization will provide crucial data to help inform future toxicological, epidemiological, and biological studies of any long-term effects related to the inhalation of aluminum dust and nanomaterials.

麦金太尔粉末（MP）是一种精细研磨的铝粉，在1943年至1979年之间用于预防矽肺病。矽肺病是由于吸入结晶硅尘而引起的一种慢性肺部疾病，在此期间在加拿大采矿业中很普遍。麦金太尔研究基金会开发了MP，并为其申请了专利，并制作了MP，并将其分发给加拿大，美国，墨西哥，智利，比利时刚果和西澳大利亚的持牌人。据估计，在加拿大安大略省，1943年至1979年之间至少有27,500名矿工接触了MP。本研究旨在检查MP的两种变体（浅灰色和黑色）的化学和物理特性。p <0.001）。X射线衍射仪显示，虽然氢氧化铝在两种变化中均占铝形态的主导地位，但黑色MP中较高的总铝含量归因于元素铝的比例更高。物理表征（使用电子显微镜，光学显微镜和动态光散射）表明，浅灰色MP由直径范围为5 nm至5 µm的颗粒组成。原子力显微镜显示，纳米颗粒范围（<100 nm）中的浅灰色MP颗粒的模式为5到10 nm。因此，吸入的较小的MP纳米颗粒可能会通过血液和淋巴液循环转运到包括大脑在内的许多不同器官。吸入的较大MP颗粒也可能沉积在肺组织上，并可能因免疫激活引起的炎症反应而对健康产生潜在影响。MP的表征将提供关键数据，以帮助将来对与铝粉尘和纳米材料吸入有关的任何长期影响进行毒理学，流行病学和生物学研究。