Sisco Edward, Staymates Matthew E, Burns Amber
National Institute of Standards and Technology.
Maryland State Police Forensic Sciences Division.
Forensic Chem. 2020;18. doi: https://doi.org/10.1016/j.forc.2020.100232.
Recent work has shown that detectable levels of drugs exists on nearly all surfaces within a forensic laboratory - especially within the drug chemistry unit. This is an expected occurrence due to the handling and opening of drug evidence that contains powder material. The process of opening evidence, which produces aerosolized particulate that can settle on surfaces throughout the lab, has never been visualized. This work presents the first attempt to visualize the spread of particulate throughout the laboratory during the analysis of drug evidence and introduces an easy to implement approach laboratories can use to evaluate their specific protocols. By creating two simulated bricks of drugs that contained fluorescent particles, the spread of particulate was able to be monitored throughout the evidence handling process up to and including cleaning of surfaces after analysis. The protocols in this work, showed the spread of particulate, prior to cleaning, to be quite extensive, with transfer onto surfaces and items that were handled. In this study, cleaning with methanol after processing the evidence was shown to be effective at removing nearly all particulate that was released in the process. The use of visualization techniques such as this demonstrate promise for helping laboratories identify processes in their own protocols that may contribute to drug background levels and educate forensic chemists how trace residues spread.
最近的研究表明,法医实验室几乎所有表面都存在可检测水平的药物,尤其是在药物化学部门。由于处理和打开含有粉末物质的毒品证据,这是一种预期的现象。打开证据的过程会产生可雾化的颗粒,这些颗粒会沉积在实验室的各个表面上,但这一过程从未被可视化过。这项工作首次尝试在毒品证据分析过程中可视化颗粒在整个实验室中的传播,并介绍了一种易于实施的方法,实验室可以用它来评估自己的特定流程。通过制作两块含有荧光颗粒的模拟毒品砖,能够在整个证据处理过程中监测颗粒的传播,直至并包括分析后表面的清洁。这项工作中的流程显示,在清洁之前,颗粒的传播范围相当广泛,会转移到被处理的表面和物品上。在这项研究中,证据处理后用甲醇清洗被证明能有效去除过程中释放的几乎所有颗粒。使用这样的可视化技术有望帮助实验室识别其自身流程中可能导致药物背景水平的过程,并教育法医化学家微量残留物是如何传播的。