Toxicological analysis of some cases can be complicated by poor sample quality caused by decomposition. Although heroin-related deaths have been researched extensively, the interpretation of toxicology findings in these cases is challenging, especially in instances where blood samples are unavailable. Thus, it is important to develop analytical methods for different sample types. In this study. a method for the quantification of 6-monoacetylmorphine, 6-acetylcodeine, morphine, and codeine in postmortem stomach wall tissue using liquid chromatography coupled with tandem mass spectrometry was developed and validated. All calibration curves prepared with the stomach wall tissue were linear and ranged from 0.5−1000 ng/g with determination coefficients of >0.99 and a lower limit of quantification of 1.0 ng/g. The coefficients of variation for within-run precision and between-run precision were <9%. Matrix effects of stomach wall tissues and their extraction recoveries were investigated and ranged from −19% to +17% and 76% to 80%, respectively. Among the 16 analyzed heroin-related death cases, 6-monoacetylmorphine, 6-acetylcodeine, morphine, and codeine were detected in 75%, 31%, 100%, and 94% of all stomach wall tissues with median concentrations of 90 ng/g, 20 ng/g, 140 ng/g, and 30 ng/g, respectively. This study provides new data on the distribution of 6-monoacetylmorphine, 6-Acetylcodeine, morphine, and codeine in postmortem stomach wall tissue and suggests the usefulness of alternative matrices for investigating heroin-related fatalities when blood samples are unavailable. In addition, the prevalence of 6-monoacetylmorphine in the stomach wall tissue was higher than that in the liver and kidney tissues.
Keywords: LC-MS/MS; forensic toxicology; opiates; opioids; postmortem; stomach wall tissue.