Laurentian University, Ontario, Canada.
Health Canada, Ottawa, Ontario, Canada.
J Occup Environ Hyg. 2019 Nov;16(11):745-756. doi: 10.1080/15459624.2019.1657581. Epub 2019 Sep 18.
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 ( < 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，曾于 1943 年至 1979 年期间用作矽肺的预防剂。矽肺是一种由吸入结晶二氧化硅粉尘引起的慢性肺部疾病，在这段时间内，加拿大采矿业普遍存在这种疾病。麦金太尔研究基金会开发、获得专利并生产了 MP，并将其分发给加拿大、美国、墨西哥、智利、比属刚果和西澳大利亚的被许可方。在加拿大安大略省，据估计，至少有 27500 名矿工在 1943 年至 1979 年期间接触过 MP。本研究旨在检查两种变体的 MP（浅灰色和黑色）的化学和物理特性。化学分析（使用 X 射线荧光和电感耦合等离子体方法）表明，黑色 MP 中铝和金属杂质的浓度明显高于浅灰色 MP（<0.001）。X 射线衍射表明，虽然两种变体中铝的形态主要由氢氧化铝主导，但黑色 MP 中总铝含量较高是由于元素铝的比例更大。物理特性分析（使用电子显微镜、光学显微镜和动态光散射）表明，浅灰色 MP 由直径从 5nm 到 5μm 的颗粒组成。原子力显微镜显示，纳米颗粒范围内（<100nm）的浅灰色 MP 颗粒的模式在 5nm 至 10nm 之间。因此，吸入的较小 MP 纳米颗粒可能通过血液和淋巴液循环被运送到许多不同的器官，包括大脑。吸入的较大 MP 颗粒也可能沉积在肺部组织上，并且免疫激活可能会引发炎症反应，从而产生潜在的健康影响。这种 MP 特性将为未来与吸入铝粉尘和纳米材料相关的任何长期影响的毒理学、流行病学和生物学研究提供关键数据。
