Illicit drugs in alternative biological specimens: a case report

Postmortem tissues (e.g. liver, kidney) have been long used in forensic applications especially in those cases where blood is unavailable. The aim of this paper is to demonstrate the importance of the information provided to the forensic toxicologist at the time of carrying out the toxicological analysis, especially in cases where the samples commonly used in forensic toxicology are unavailable. This work describes the toxicological findings in a violent death resulting from a man who was hit by a train. Vitreous humor, liver and kidney were sent for toxicological analysis, once it was not possible to obtain blood and urine. The validated procedures used in the routine casework of Forensic Toxicology Laboratory of the Centre Branch of the National Institute of Legal Medicine, were applied in the analysis of liver, kidney and vitreous humor, using gas chromatography-mass spectrometry after solid-phase extraction and gas chromatography-flame ionization detector for the analysis of drugs of abuse and ethanol, respectively. Morphine, codeine, cocaine, benzoylecgonine and ecgonine methyl ester were found in the liver and in the kidney and no ethanol was found in the vitreous humor. The method validation included the study of specificity, selectivity, limits of detection, recovery and carryover. Although blood and urine are the most common and preferred matrices used for toxicological studies involving drugs of abuse, sometimes the choice of specimen is determined by the case under investigation. The forensic pathologist must be aware that relevant information must be provided so that the toxicological analysis can be conducted in accordance with case history, particularly when the only samples available for analysis are these "unconventional" specimens, since the interpretation of the obtained results is more difficult.