γ-Hydroxybutyrate Concentrations in Pre- and Postmortem Blood and Urine

With γ-hydroxybutyrate (GHB) becoming popular as a drug of abuse in the US and elsewhere (1), we are receiving increasing requests for the analytical determination of GHB in blood or urine in criminal investigations, especially in sexual assault cases. In a recent report of a fatal poisoning with GHB, the victim had a postmortem blood GHB concentration of 27 mg/L (2), and another three GHB-related fatalities were reported with postmortem blood GHB concentrations of 52–121 mg/L (3). As a part of a validation study before instituting a GC-MS method described by others (4), we tested for GHB presence in a series of forensic specimens submitted routinely to us by law enforcement agencies and medical examiner offices in cases not known to be GHB-related. No GHB was detected (detection limit, 1 mg/L) in the blood or urine of living persons or in postmortem urine, but very substantial concentrations, ranging from 3.2 to 168 mg/L, were found in 15 of 20 autopsy blood specimens (Table 1). Reanalysis of these 20 blood specimens by gas chromatography with flame-ionization detection on a packed column (5) gave similar qualitative and quantitative results.