Postmortem distribution and redistribution of synthetic cathinones

Purpose: Synthetic cathinones are powerful psychostimulants that have been associated with fatal intoxications. Because of changes that take place following death, postmortem toxicology results require careful interpretation. The purpose of this study was to evaluate the distribution of synthetic cathinones in postmortem specimens in a series of 50 cathinone-positive fatalities. Methods: Liquid chromatography–quadrupole time-of-flight-mass spectrometry was used to quantitatively identify cathinones in central blood (n = 51), peripheral blood (n = 31), urine (n = 33), liver (n = 22), vitreous humor (n = 1) and stomach contents (n = 1). The distribution of cathinones and the potential for postmortem redistribution was assessed. Results: Among the 50 cases investigated, a total of nine synthetic cathinones (α-PVP, ethylone, methylone, butylone, MDPV, methedrone, pentylone, 4-MEC, and MDPBP) were identified in 139 specimens. The number of specimens per case ranged from one to six. In cases that included central blood or liver, together with a peripheral blood source, the central/peripheral (C/P) or liver/peripheral (L/P) ratio was calculated to estimate the potential for postmortem redistribution (n = 21 C/P; n = 11 L/P). Methylone and ethylone appeared to exhibit the greatest potential for postmortem redistribution, producing C/P ratios of 4.0 (1.5–6.1) and 2.9 (0.5–9.2), respectively. In contrast, the C/P ratio for α-PVP was 1.1 (0.5–1.9). Differences in C/P ratios between methylone and α-PVP were statistically significant (α = 0.05). Conclusions: Although synthetic cathinones may exhibit low to moderate postmortem redistribution, significant variability exists due to site- and time-dependent factors. This, in combination with their overall instability, necessitates careful interpretation of postmortem toxicology results.