Net Weights: Visualizing and Quantifying their Contribution to Drug Background Levels in Forensic Laboratories.
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ABSTRACT:
SUBMITTER: Sisco E
PROVIDER: S-EPMC8209848 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Identifying and quantifying the drug background in operational environments such as forensic laboratories is an emerging body of research. Knowing these levels is crucial to addressing issues like occupational exposure risk - due to the emergence of potent novel psychoactive substances and synthetic opioids - and data integrity - due to improvements in instrument sensitivity. The work presented here builds upon a prior study to provide a broader representation of the average drug background levels found on surfaces in forensic laboratories. Over 700 samples from 20 laboratories were collected, extracted, and analyzed quantitatively using LC-MS/MS, and qualitatively using TD-DART-MS. Quantitative analysis by LC-MS/MS included a panel of 18 drugs while the non-targeted qualitative analysis by TD-DART-MS screened for over three hundred drugs and excipients. The study focused primarily on surfaces within the drug unit and evidence receiving area of the laboratories, but also investigated other operational units (crime scene, drug interdiction, latent prints, and toxicology) as well as report writing. Background levels were highest within the drug unit of the laboratory, though detectable (tens of nanograms) levels were observed in nearly all sampled areas. The data from this expanded study plays a critical role in addressing laboratory concerns such as establishing drug identification reporting limits for new instrumentation and establishing new workflow or cleaning protocols while also providing a more comprehensive dataset for general environmental background studies.
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2021-01-31 | E-MTAB-9916 | biostudies-arrayexpress
Project description:Understanding the structural adaptation and signaling of adhesion sites in response to mechanical stimuli requires in situ characterization of the dynamic activation of a large number of adhesion components. Here, we review high-resolution live cell imaging approaches to measure forces, assembly, and interaction of adhesion components, and the activation of adhesion-mediated signals. We conclude by outlining computational multiplexing as a framework for the integration of these data into comprehensive models of adhesion signaling pathways.
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Project description:Regular proficiency testing of forensic examiners is required at accredited laboratories and widely accepted as an important component of a functioning quality assurance program. Yet, unlike in other testing industries, the majority of forensic laboratories testing programs rely entirely on declared proficiency tests. Some laboratories, primarily federal forensic facilities, have adopted blind proficiency tests, which are also used in the medical and drug testing industries. Blind tests offer advantages. They must resemble actual cases, can test the entire laboratory pipeline, avoid changes in behavior from an examiner knowing they are being tested, and are one of the only methods that can detect misconduct. However, the forensic context present both logistical and cultural obstacles to the implementation of blind proficiency tests. In November 2018, we convened a meeting of directors and quality assurance managers of local and state laboratories to discuss obstacles to the adoption of blind testing and assess successful and potential strategies to overcome them. Here, we compare the situation in forensic science to other testing disciplines, identifying obstacles to the implementation of blind proficiency testing in forensic contexts, and proposing ways to address those issues and increase the ecological validity of proficiency tests at forensic laboratories.
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Project description:Background Despite the recent trend toward developing and applying quality control measures in the forensic science disciplines, there is a heightened interest to efforts to ameliorate disparate quality among laboratories through the enforcement of standards and best practices.Objective This protocol aims to set up the Arab Forensic Laboratories Accreditation Center (AFLAC) to act as a key driving legal force for accreditation of the different forensic laboratories in the Arab region.Methods Upon its development, the Forensic Laboratory-Arabian Gate (FLAG) platform will serve as a preliminary stage for the AFLAC, and 2 preparatory steps will be achieved through the FLAG platform: the first one is a scoping study to analyze the international guidelines regarding the forensic laboratory practices in different specialties, and the second one is mapping surveys to explore how the international and national guidelines are translated into practice in Arab forensic laboratories. Development of the Arab forensic laboratories accreditation center will be initiated by building the AFLAC quality management system, which comprises formation of the forensic science committees to achieve the standards required for accreditation in each discipline. This will be followed by the attainment of regional accreditation recognition of the Arab Accreditation Cooperation (ARAC) and the International Laboratory Accreditation Cooperation. This recognition necessitates achieving International Organization for Standardization/International Electrotechnical Commission 17011 standard requirements prior to official application to the ARAC.Results The first phase of our work (the FLAG platform) began in February 2022 and is expected to end in December 2022. The FLAG platform was proposed to the Arab Society of Forensic Sciences and Forensic Medicine in March 2022, and we received approval to host this web development project. Subsequent phases are anticipated to begin in January 2023 and are expected to end in 2025.Conclusions This work describes our approach to provide a valuable tool for forensic laboratory accreditation services to promote the best practice and its consistency in the field of forensic sciences in the Arab region.International registered report identifier (irrid)PRR1-10.2196/36778.
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