Enhanced selectivity in the determination of delta9-tetrahydrocannabinol and two major metabolites in serum using ion-trap GC-MS-MS

Cannabinoids were extracted from serum with C18 SPE cartridges and analyzed as their trimethylsilyl (TMS) derivatives. A benchtop gas chromatography-tandem mass spectrometry (GC-MS-MS) system based on an ion trap with external ionization was used. Quantitation was done in relation to trideuterated internal standards in dual MS-MS mode. Confirmation of the identity for the three compounds of interest, delta9-tetrahydrocannabinol (THC), 11-hydroxy-delta9-tetrahydrocannabinol (11-OH-THC), and 11-nor-9-carboxy-delta9-tetrahydrocannabinol (THCCOOH), was achieved by registering the daughter spectra in full scan mode. It was possible to identify the three compounds at concentrations down to 0.25 microg/L for THC, 0.5 microg/L for 11-OH-THC, and < 2.5 microg/L for THCCOOH by comparison with reference spectra. The limits of quantitation are better than 2 microg/L for THC, 5 microg/L for 11-OH-THC, and 8 microg/L for THCCOOH. The within-run and day-to-day precision for the three analytes were very similar and ranged from 4.2 to 10.4%.

[Arterial and venous alcohol elimination in 10 polytrauma patients]

Alcohol elimination was examined in 10 patients involved in accidents while intoxicated. The influence of trauma, particularly polytrauma resulting in haemorrhage shock and its therapeutic treatment were analysed. The blood alcohol concentrations were determined according to the usual forensic criteria (2 alcohol dehydrogenase and 2 gas chromatography measurements). Observation periods ranged from 3 hours 45 minutes to 12 hours 35 minutes, with blood being drawn at intervals ranging from 45 minutes to 185 minutes (on average 70 minutes). Results of two patients (delta 60 = 0.22/1000/h and 0.28/1000/h) who only had 3 venous drawn and results of a deceased patient from whom only four arterial samples could be obtained (beta 60 = 0.21/1000/h) were disregarded when working out the average values. The blood alcohol curve plateaued in the case of the deceased patient as well as in the case of a patient whose hepatic circulation was curtailed for approximately half an hour during surgery. The blood alcohol curves for the remaining patients for uniformly linear with beta 60 values between 0.17/1000/h and 0.21/1000/h (mean = 0.18/1000/h +/- 0.01) in arterial samples and 0.18/1000/h and 0.21/1000/h (mean = 0.18/1000/h +/- 0.01) in venous samples. Given our results and the existing literature, we feel that retrograde calculations of the BAC can be justified in patients with polytrauma, despite the small number of patients included in the study. Naturally, the usual forensic criteria have to be taken into account, as well as individual situations. Examples that can be mentioned here are liver failure or curtailment of hepatic circulation during surgery.

Heavy metals, chlorinated pesticides and polychlorinated biphenyls in sudden infant death syndrome (SIDS)

The concentrations of lead in blood and of cadmium and mercury in kidney tissue were determined by atomic absorption spectrometry in cases in SIDS and a control group containing cases of known causes of death. SIDS cases were split into groups from urban and rural areas and areas highly polluted with lead and zinc (sites of lead and zinc works). Neither the concentration of lead in blood (median 26.5 to 50.0 micrograms/l), nor the concentration of cadmium (median 24.0 to 44.0 micrograms/kg ww) or mercury (43.0 to 69.0 micrograms/kg ww) showed significant differences between the groups. In addition the concentrations of persistent chlorohydrocarbons (hexachlorbenzene; alpha, beta and gamma hexachlorcyclohexane; heptachlorepoxide; dieldrine; total DDT; polychlorinated biphenyls) were measured in subcutaneous fatty tissue in SIDS cases from rural and urban areas and in a control group. These substances also showed no significant concentration differences in cases of SIDS.

Lethal intoxication with diphenhydramine. Report of a case with analytical follow-up

A fatal monointoxication with diphenhydramine in a male 28 year old is reported. The patient went into hyperpyrexia and tachycardia and died from sudden cardiac arrest. Hemorrhagic pulmonary edema and renal shock were the most prominent pathomorphological findings. At the time of death, the concentration of diphenhydramine was 5 mg/l plasma and was particularly high in the lungs (55 mg/kg) and kidneys (50 mg/kg).