In vivo measurement of arsenic, aluminum, indium and fluorine

采矿和冶炼对加拿大经济极为重要。2000年，加拿大出口了价值480亿美元的非燃料矿物和矿物产品，是世界上最大的铀生产国，第三大铜生产国，并生产锌、铅、镉、铂、铟、铝、金和其他金属。对这一行业的经济依赖意味着有大量的加拿大工人暴露于潜在的有毒元素，许多加拿大人在环境中暴露的水平较低。 已知接触的工人通常由雇主通过血液和尿液测量进行监测。如果工人的辐射水平超过某些预先设定的限度，将被从潜在的高辐射环境中移除，直到他们的辐射水平下降。然而，仅测量血液或尿液并不能单独说明外源性和内源性接触，这可能使风险的解释变得复杂。这也使得管理具有广泛就业历史的工人变得困难，因为他们通常具有该元素的身体储存，即使在没有外部暴露的情况下，也可以保持血液和尿液升高。 此外，没有对公众的接触情况进行例行监测。如果怀疑接触有毒元素，可以进行血液和尿液测量。然而，这些通常仅表明最近的接触，而接触可能发生在健康后果之前数月或数年，许多健康影响是长期或累积接触的结果。可以采取活检来增加更多的信息，但这些充其量是不舒服的，并且可能不能代表整个器官内的水平。因此，在健康管理中，有一个角色的技术，可以非侵入性地测量体内的有毒元素的水平，无论是在危险的器官或器官中的元素是存储。本提案的目的是开发物理技术的非侵入性体内测量四种元素：砷，铟，铝和氟。将采用三种技术：X射线荧光（XRF）、中子活化分析（NAA）和核磁共振（NMR）。

Mining and smelting are extremely important to the Canadian economy. Canada exported $48 billion worth of non-fuel minerals and mineral products in 2000 and is the world's largest producer of uranium, the third largest producer of copper, and produces zinc, lead, cadmium, platinum, indium, aluminum, gold... The economic dependence on this industry means that there are large numbers of Canadian workers exposed to potentially toxic elements and many Canadians exposed environmentally at lower levels.  Workers who are known to be exposed are generally monitored by their employer via blood and urine measurements. Workers whose levels increase above certain pre-set limits will be removed from potentially high exposure situations until their levels fall. However, measurement of blood or urine alone does not allow exogenous and endogenous exposures to be separately accounted for, and this can make the interpretation of risk complicated. It also makes the management of workers with extensive employment histories difficult, as they often have body stores of the element which can keep blood and urines elevated even in the absence of external exposure.  In addition, members of the public are not routinely monitored for their exposure. If exposure to a toxic element is suspected, blood and urine measurements can be performed. However, these usually only indicate recent exposure whereas the exposure may have taken place months or years prior  to the health consequence, and many health effects are a result of chronic or cumulative exposure. Biopsies can be taken to add further information, but these are uncomfortable at best, and may not be representative of the level within a whole organ. There is therefore a role in health management for techniques which can non-invasively measure in vivo the level of a toxic element either in organs at risk or in organs where the element is stored.The aim of this proposal is to develop physics techniques for the non-invasive in vivo measurement of four elements; arsenic, indium, aluminum and fluorine. Three techniques will be employed; x-ray fluorescence (XRF), neutron activation analysis (NAA) and Nuclear Magnetic Resonance (NMR).