New and improved methods for risk assessment of food and pharmaceutical products safety and for forensic analysis

为了测量固体食品和药品中铅和砷等潜在有害元素的浓度，政府机构首先将它们溶解，这涉及多个步骤。这不仅需要时间和苛刻的化学品，而且还增加了污染的可能性(假阳性)或可能导致某些元素的损失(假阴性)。此外，这种方法不提供任何关于每种元素的化学形态的信息，而这些元素的化学形态决定了毒性。最关键的是，它也没有提供任何关于生物可及性的信息，即在胃肠道中的溶解度。然而，毒物只有在进入血液时才是一个安全问题，在那里它可能会发挥其毒性作用。拟议的研究计划将涉及开发简单的分析方法，以快速确定固体中存在的每种元素的水平。如果一种元素的水平对人类健康构成潜在危险，那么将使用另一种相对快速的分析方法来测量生物可获得的部分。最后，如果生物可及组分包含不同化学形态的元素，将使用另一种方法来区分和量化毒性和毒性较低的形式，以真正评估风险。快速和具有成本效益地获得有关食品和药品中元素形态和生物可获得浓度的信息，将使毒理学研究能够确定不同元素之间是否存在协同或拮抗效应。这将授权加拿大当局将食品和药品中元素(甚至特定元素形式)的水平控制在安全水平，从而减少它们的免疫毒理影响。在一个相关的项目中，洗涤或浸泡食物的效果将在其他谷物上进行测试，以找出何时可以更安全地食用。众所周知，洗涤或浸泡食物可以去除大米中的一些有毒砷。烹饪的效果，包括烹饪食物的方式(如煮沸、烘烤、加压烹饪等)关于主食(大米、小麦、玉米、面包等)中的生物可及分数和化学形态将进行研究，以确定烹饪是否有有益的影响。在第三个相关项目中，将优化快速分析技术，以辨别各种法医样本(头部毛发、肇事逃逸案件中遗留的汽车油漆碎片、指甲等)，从而为警察机构的武器库增加一个新的工具，帮助他们破案。执法机构，包括加拿大皇家骑警，将能够轻松和具有成本效益地实施开发的方法。至少9名研究生和25名本科生将参与这项研究的不同方面，这项研究将使用现代仪器和协议进行，试图确保加拿大人的安全。

To measure the concentration of potentially harmful elements such as lead and arsenic in solid food and pharmaceutical products, government agencies first dissolve them, which involves multiple steps. This not only takes time and requires harsh chemicals but also increases the likelihood of contamination (false positive) or may result in the loss of some of the elements (false negative). In addition, this approach does not provide any information on the chemical form of each element, which determines toxicity. Most critically, it also does not provide any information on bio-accessibility, i.e. solubility in the gastrointestinal tract. Yet, a poison is only a safety concern if it enters the blood stream, where it may exert its toxic effect. The proposed research program will involve the development of simple analysis methods that quickly determine the level of each element present in a solid. If the level of an element poses a potential danger to human health, another relatively fast analysis method will then be used to measure the fraction that is bio-accessible. Finally, if the bio-accessible fraction contains different chemical forms of the elements, another method will be used to distinguish and quantify the toxic and less toxic forms to truly assess the risk. Rapid and cost-effective acquisition of information on both element forms and bio-accessible concentrations in foods and pharmaceutical products will enable toxicological studies to establish if a synergistic or antagonistic effect exists between different elements. This will empower Canadian authorities to regulate the levels of elements (and perhaps even specific element forms) in food and pharmaceutical products at safe levels, thereby reducing their immuno-toxicological effects. In a related project, the effect of washing or soaking food, which is known to remove some toxic arsenic from rice, will be tested on other grains to find out when it can make them safer for consumption. The effect of cooking, including the manner in which food is cooked (such as boiling, toasting, pressure cooking, etc.) on the bio-accessible fraction and the chemical forms present in staple food (rice, wheat, corn, bread, etc.) will be studied to establish if cooking has a beneficial effect. In a third related project, a quick analysis technique will be optimized for the discrimination of various forensic samples (head hair, automotive paint fragments left in hit-and-run cases, finger nails, etc.), thereby adding a new tool to the arsenal of police agencies to help them solve crimes. Law enforcement agencies, including the Royal Canadian Mounted Police, will be able to implement the methods developed easily and cost-effectively. At least 9 graduate and 25 undergraduate students will participate in different aspects of this research, which will be carried out using modern instruments and protocols in an attempt to guarantee the safety and security of Canadians.