ROLE OF METABOLITES IN AVIATION FORENSIC TOXICOLOGY

In aviation accident investigations, specimens from fatal aircraft vic tims are analyzed for drugs. The presence of drugs suggests possible a ssociated medical conditions for which they might have been taken. As drugs are mostly present in therapeutic to subtherapeutic levels in av iation forensic toxicology cases, determination of parent drugs and th eir metabolites in multispecimens is of significance. Although chemica lly reactive metabolites are difficult to detect, physiologically acti ve and inactive metabolites can be analyzed. Selective and sensitive t echniques are available, but unavailability of metabolite reference st andards, endogenous substance interference, and low tissue metabolite levels limit the analyses. However, the majority of primary metabolite s can be effectively characterized/quantitated. Demonstrating the pres ence of drug (e.g., terfenadine, cocaine, THC) metabolites provides a compelling evidence for exposure to the parent drug and facilitates in terpretation of results, particularly when the metabolites are active. Such analyses are not as helpful if the metabolites are also availabl e as drugs (e.g., diazepam, temazepam, oxazepam).