Characterization of Crystalline Silica Polymorphs by Infrared Spectroscopy

结晶二氧化硅(如石英)通常存在于采矿、制造等职业环境中 和构造被执行。据估计，至少有170万北美工人有可能 暴露在可呼吸的结晶二氧化硅粉尘中。这样的暴露与患上往往致命的 肺病，包括矽肺和肺癌。因此，二氧化硅粉尘的有效采样和量化 重要的是确保安全的工作环境，遵守职业接触限值。中的采样 工作场所包括通过旋风分离器将空气吸入滤芯以捕获可呼吸的粉尘，然后 用红外光谱或X射线衍射法进行定量。许多实验室，包括OSHTECH，都雇佣了一种 透射式红外法有各种优点，但需要繁琐的样品制备。 该项目旨在开发一种简化的分析方法，用于晶态二氧化硅的定量 红外光谱学。我们将探索一系列替代红外技术来准确量化 结晶二氧化硅不需要目前应用的方法进行多步骤的制备和操作。我们会 使用透射法、漫反射法、衰减全反射法和 光声红外光谱。我们的最终目标是开发一种非破坏性的方法，具有 检测限与现有方法相当，甚至更好。一个成功的项目将有助于卫生 专业人士和监管机构，以更好地保护加拿大工人。

Crystalline silica (such as quartz) is often present in occupational environments where mining, manufacturing and construction are performed. It is estimated that at least 1.7 million North American workers are potentially exposed to respirable dust of crystalline silica. Such exposure is associated with the development of often-fatal lung diseases including silicosis and lung cancer. Efficient sampling and quantification of silica dust is thus important to ensure a safe working environment that respects the occupational exposure limit. Sampling in the workplace consists of drawing air through a cyclone onto a filter cassette to trap respirable dust followed by quantification by infrared spectroscopy or X-ray diffraction. Many laboratories, OSHTECH included, employ a transmission infrared method that has various advantages but that requires cumbersome sample preparation. This project aims to develop a simplified analytical protocol for the quantification of crystalline silica by infrared spectroscopy. We will explore a series of alternative infrared techniques to accurately quantify crystalline silica without multistep preparation and manipulation of the currently applied method. We will conduct measurements using methods such as transmission, diffuse reflection, attenuated total reflection, and photoacoustic infrared spectroscopy. Our ultimate objective is to develop a non-destructive method with a detection limit equal to or even better than that of existing methods. A successful project will help hygiene professionals and regulators to better protect Canadian workers.