IN VIVO COINCIDENCE XRF MEASUREMENTS FOR HEAVY METALS

X射线荧光(XRF)是测量人体和 体内重金属的器官负荷。但是，要求的精度 对长期、低水平接触这些金属的人群进行筛查， 尤其是铅和汞，比 目前的方法是可以实现的。这项提案描述了一种创新的 XRF的变化，可以提供一到一的精度提高 比目前的技术高出两个数量级。这是通过以下方式实现的 将信号下的背景降低1000万倍，而 信号本身只减少了100。第一阶段将证明其可行性 这种方法的重要性。 来自社会各阶层的300至400万名儿童暴露在 环境中铅的浓度使它们处于危险之中 对健康的不利影响。对汞的调查无处不在 因为许多食物，特别是海鲜，都含有大量的 水星。有100多个独立的职业可能 暴露于铅或汞。然而，目前还没有可用的工具来衡量 体内或器官负荷的铅或汞，具有足够的精度 筛查长期、低水平暴露人群。建议数 这种方法将使开发这样一个工具成为可能。

X-ray fluorescence (XRF) is the most precise method of measuring body and organ burdens of heavy metals in vivo. However, the required precision for screening of chronically, low-level exposed populations for these metals, in particular lead and mercury, is between 5 and 20 times greater than achievable by current methods. This proposal describes an innovative variation of XRF which can provide an improvement in precision of one to two orders of magnitude over present technology. This is achieved by reducing the background under the signal by a factor of 10 million, while reducing the signal itself by only 100. Phase I will prove the feasibility of the approach. Three to four million young children from all levels of society are exposed to environmental sources of lead at concentrations that place them at risk of adverse health effects. The investigation of mercury is ubiquitous since many foods, and especially seafoods, contain significant amounts of mercury. There are over 100 independent occupations with possible exposures to lead or mercury. Yet, there is no tool available to measure body or organ burdens of lead or mercury with sufficient precision for screening chronically, low-level exposed populations. The proposed approach will enable the development of such a tool.