First Seven Years (1991-1998) of the FAA's Postmortem Forensic Toxicology Proficiency-Testing Program

摘要

Postmortem biosamples from the victims of aviation accidents are submitted to the Civil Aeromedical Institute (CAMI) for forensic toxicology, wherein acquiring accurate and authentic analytical data is the primary objective. Adherence to quality assurance/quality control (QMQC) procedures is essential to achieve that objective, and proficiency-testing (PT) is an integral part of QA/QC of laboratories. However, there was previously no suitable PT program that could address the complexity of forensic toxicology. Existing PT programs do not include decomposed samples and solid tissues, and the majority of aviation (and to some extent, even medical examiner and coroner) case samples are putrid and of multiple types. Therefore, CAMI in July 1991 started such a needed PT program. This program is used to (i) professionally develop and maintain technical currency on a voluntary, interlaboratory, and self-evaluation basis and (ii) quantifiably assess methods in the absence and presence of interfering substances. There are currently about 30 laboratories in the program, including CAMI's Toxicology and Accident Research Laboratory. Functioning under various governmental/non-governmental agencies and academic institutions, these laboratories represent a broad cross- section of the country. PT samples are distributed quarterly, and result summaries are sent to the participants, while maintaining their anonymity. Since the inception of the program, 28 PT samples encompassing whole blood, plasma, urine, kidney, or liver, with (or without) drugs and common chemicals (nicotine, caffeine, beta- phenylethylamine, etc.) have been evaluated by the participants. Analytical findings were generally consistent with the anticipated values, but they were dependent on the nature and conditions of the specimens and types of the added analytes. Some incidences of false positives of concern were noted, as well.