EXPERIMENTAL PNEUMOCONIOSIS OF SANDBLASTING SUBSTITUTES

使用喷砂清洁钢结构在应用油漆之前， 与严重和快速进展的硅肺有关。 高发病率 和死亡率已经注意到在几年的接触。 的 美国劳工部估计， 喷砂要78000 认识到这些危险， 在欧洲和澳大利亚禁止喷砂;在美国，砂 替代品正在越来越多地被使用。 它们是从煤中提炼出来的 灰渣和炉渣从冶炼炉，并包括各种 Fe、Al、Ca、Mg和Ti的无定形硅酸盐的比例。 自由 二氧化硅含量仅为0.03%。 本项目的目的是开发一种大鼠模型，以评估 沙子替代品的肺纤维化潜力。 纤维化效应 长期暴露于替代品将在两个正常的 和矽肺大鼠。 将在一组中诱导矽肺，然后 第二组将只暴露于 替身 暴露后，将对两组进行额外的随访， 十二个月。 将维持适当的对照大鼠， 比较。 将大鼠依次处死， 胶原蛋白的生化测定和组织矿物质含量评估。 这项研究将首次评估这些替代品的安全性。 我们相信这种大鼠模型将在描绘和 预测喷砂工的潜在职业危害， 而且之前没有硅肺 职业暴露标准是 基于这样的假设，即任何特定代理人的风险不 受其他环境因素的影响。 本研究将 提供有关生物制品导致肺纤维化风险的重要信息 不同吸入剂之间的相互作用，这可能会影响 职业标准的未来发展。 更具体地说， 项目将证明矽肺进展的风险增加，如果 硅砂喷砂工使用这些替代品。

The use of sandblasting to clean steel structures before applying paint is associated with severe and rapidly progressive silicosis. High morbidity and mortality rates have been noted within a few years of exposure. The U.S. Department of Labor has estimated the number of workers engaged in sandblasting to be 78,000. Recognition of these hazards led to the prohibition of sandblasting in Europe and Australia; in the U.S., sand substitutes are now increasingly being used. They are derived from coal ash residues and slag from smelting furnaces, and comprise various proportions of amorphous silicates of Fe, Al, Ca, Mg and Ti. The free silica content is only 0.03%. The objective of this project is to develop a rat model to assess the pulmonary fibrogenic potential of sand substitutes. Fibrotic effect from prolonged exposure to the substitutes will be investigated in both normal and silicotic rats. Silicosis will be induced in one group, followed by exposure to the substitute; the second group will be exposed only to the substitute. After exposure, both groups will be followed for an additional twelve months. Appropriate control rats will be maintained for comparisons. Rats will be sequentially sacrificed for histologic, biochemical assay of collagen, and tissue mineral content evaluations. This study will assess for the first time the safety of these substitutes. We believe this rat model will have application in delineating and predicting the potential occupational hazards for abrasive blasters with and without pre-existing silicosis. Occupational exposure standards are based on the assumption that the risk of any particular agent is not influenced by exposure to other environmental factors. This study will provide important information on the risk of lung fibrosis from biologic interactions between different inhaled agents, which could affect the future development of occupational standards. More specifically, this project will demonstrate increased risk of progression of silicosis if silicotic sandblasters use these substitutes.