A case of attempted murder using blue monkshood due to unfulfilled desires

Abstract

After eating the remains of a noodle soup, two dogs almost immediately showed unspecific symptoms of poisoning, like vomiting, drooling and seizures. The dogs’ symptoms of poisoning were described as severe and one of the dogs almost died, according to the police informations. Unfortunately, appropriate informations from the veterinarian were not available to us. In addition, a blister with blood pressure medication had disappeared from the kitchen table that day. From the previous history it emerged that the affected family had already been stalked and terrorized for months by an unknown person and the dogs had already been poisoned with a sort of slug pellets months before. For analysis, initially only vomit from the dogs and small remnants of the noodle soup were available. During investigations, it was possible to narrow down a suspect who had already made sort of attempted sexual approach to the husband of the family but was rejected. The history of the suspect revealed that he had previously served a prison sentence for attempted murder using arsenic compounds (calcium arsenate). Untargeted analyses were performed using GC-MS and LC-ToF MS. Qualification and quantification of aconitum alkaloids was performed by LC-MS/MS and LC-ToF MS on a Poroshell 120 EC-C18 column (100 × 3.0 mm, 2.7 μm) and gradient elution with 0.5 ml/min of 5 mM ammonium formate in 0.1% formic acid and acetonitrile containing 0.1% formic acid starting from 85:15 (v/v). Targeted analytes were: aconitine 646.3 → 586.2, → 526.2, → 368.1; mesaconitine 632.3 → 572.2, → 512.2, →354.1; hypaconitine 616.3 → 556.2, → 524.1, → 338.1. Results of untargeted analyses (GC-MS, LC-ToF) of dogs vomit and soup had been negative, but large analytical signals were noticed in the total ion chromatogram measured with LC-ToF. A review of the signals led to the suspicion of the aconitum alkaloids aconitine (M+ 646.3221), mesaconitine (M+ 632.3065) and hypaconitine (M+ 616.3115). Quantification in the soup remains showed high concentrations of aconitine (53 μg/g), mesaconitine (136 μg/g) and hypaconitine (18 μg/g). The hypothetical ingestion of an average plate (250 g, containing approx. 50 mg of alkaloids) of the noodle soup could have resulted in fatal poisoning. After investigations of the personal environment of the suspect which turned up negative at first, the police found out he had purchased both blue monkshood seeds and root nodules from the internet. The suspect still denied all allegations. In cases of unclear poisoning and when only little informations are available, occasionally the laborious follow up of unknown mass spectra is the key to case investigation. Also analysis for accompanying alkaloids may corroborate the hypothesis of plant-based intoxications. The suspect was found guilty of attempted murder and sentenced by the district court to life imprisonment.