In this study, two fatalities associated with the synthetic opioids AH-7921 and MT-45 are reported. Within the last few years, both compounds have emerged on the recreational drug market and are sold as “research chemicals” on the internet. In the first case, a 22-year-old woman was found dead in the bedroom of her apartment by two of her friends. A plastic bag labeled “AH-7921” was found in the apartment and the two friends stated that the deceased had consumed AH-7921 prior to her death. The woman was a known drug addict. In the second case, a 24-year-old man was found dead in his room by his mother. The deceased was sitting on a chair in front of his desk slumped over. Several bags of white powder labeled “MT-45”, “Methoxmetamine” and “Methoxphenidine” were found in his room.

Toxicological analyses of femoral blood, heart blood, liver, pericardial fluid, urine, vitreous humor and stomach content of the deceased were performed using liquid chromatography–quadrupole-time-of-flight mass spectrometry (LC–QTOF-MS). Time-of-flight mass spectrometry was carried out on an LC-Triple TOF 5600 system (AB Sciex) with electrospray ionization operated in positive mode. In the first case, additional hair analysis was performed by liquid chromatography–tandem mass spectrometry (LC–MS/MS) and LC–QTOF-MS.

In both cases, the relevant synthetic opioid could be detected in all analyzed samples. The concentration of AH-7921 was determined to be 450 μg/L in femoral blood. MT-45 was present at a concentration of 2900 μg/L in femoral blood. Besides methoxmetamine which could qualitatively be detected in femoral blood, urine and stomach content no methoxphenidine was found. In summary, deaths of the young individuals could be, by exclusion of other causes of death, attributed to the consumption of an overdose of AH-7921 and MT-45, respectively.