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N-Nitrosamine risk assessment and control have become an integral part of pharmaceutical drug product development and quality evaluation. Initial reports of nitrosamine contamination were linked with the drug substance and its manufacturing process. Subsequently, the drug product and aspects of the formulation process have shown to be relevant. Regarding specific formulation contributions to nitrosamine content in a product, one risk lies in possible interactions between nitrosating agents, derived from nitrite in excipients, and vulnerable amines, either present as moieties of the active molecule or as impurities / degradants. However, the limited validated information on nitrite levels in excipients available until now, has been an obstacle for scientists to assess the risk of nitrosamine formation in pharmaceutical products. This has driven the creation of a database to store and share such validated information. The database, maintained by Lhasa Limited, constitutes a central platform to hold the data donated by the pharmaceutical company members on the nitrite concentrations in common excipients measured with validated analytical procedures. The goal of this data sharing initiative is to provide a common framework to contextualize and estimate the risk posed by presence of nitrites to contribute to the formation of nitrosamines in drug products. The major findings from the database analyses are: (1) average nitrite content and batch to batch variance differ among excipients, (2) for solid dosage forms, the nitrite contribution is dominated by the highest formula % excipients, e.g., the fillers (diluents), which are typically used in larger proportion, and are characterized by low nitrite levels and low variability, leading to an average value of 1 µg/g nitrite in a typical formulation, (3) substantial differences in average nitrite content in batches from different excipient vendors potentially reflecting differences in source materials or processing methods for excipient manufacturing. That final point suggests that future selection of raw materials or processing by excipient manufacturers may help reduce nitrite levels in finished drug product formulations, and thus the overall risk of nitrosamine formation in cases where the product contains vulnerable amines.

Background For nearly three years, the concerns regarding trace levels of N-nitrosamines in pharmaceuticals and the associated cancer risk have significantly expanded and are a major issue facing the global pharmaceutical industry. N-nitrosodimethylamine (NDMA) found in formulations of the popular anti-diabetic drug metformin is a prominent example. This has resulted in product recalls raising the profile within the media. Issues of method robustness, sample preparation and several unexpected sources of nitrosamine contamination have been highlighted as false positive risks. It has become apparent that the identification of the root causes of artefactual formation of nitrosamines must be identified to mitigate risk associated with the analysis. Methods A comparison study between four laboratories, across three companies was designed, employing orthogonal mass spectrometric methods for the quantification of NDMA in two metformin immediate release (IR) formulations and one extended release (XR) formulation. These were 2x LC-MS/MS, GC–MS/MS and GC-HRMS. Results Good agreement of results was obtained for the IR formulations. However, we measured higher concentrations of NDMA in the XR formulation using GC-MS/MS compared to LC-MS/MS. We could show that this was due to artefactual (in situ) formation of NDMA when samples were extracted with dichloromethane. Removal of dimethylamine (DMA) and nitrite from the extracted sample or the addition of a nitrosation scavenger are shown to be effective remedies. NDMA in situ formation was not observed in 10% MeOH or acetonitrile. Conclusion Metformin pharmaceuticals contain traces of the API impurity DMA as well as inorganic nitrite from excipients. This can lead to artefactual formation of NDMA and hence false positive results if DCM is used for sample extraction. Similar artefacts are likely also in other pharmaceuticals if these contain the secondary amine precursor of the respective nitrosamine analyte.

\ud Embalmed human cadavers are an essential educational tool in forensic science and medicine. Cadavers are often embalmed to extend the period they can be used. Qualitative observations such as odours, tissue texture and colour are the only methods currently used by anatomists to assess the decomposition progress of embalmed cadavers. The aim of this study was to provide a first proof-of-concept to determine whether methylamine, putrescine, and cadaverine could be detected and monitored over time from embalmed human tissues. The hypothesis was that these three compounds would exhibit temporal trends to quantitate progress of decomposition in embalmed cadavers. Two human cadavers were embalmed using McGown solution and liver samples were analysed over 35 days. Liver samples were extracted, homogenised and derivatised to quantify the presence of methylamine, cadaverine and putrescine by gas chromatography - mass spectrometry. All three amines were detected in the tissue samples throughout the duration of the study. Both cadavers had elevated methylamine levels over putrescine and cadaverine at early stages postmortem. This was followed by peaking and reducing in different patterns by the two cadavers; however, the three compounds from a single cadaver changed in a similar pattern. The proposed experimental procedure provides a foundation for further development of quantitative biogenic amine methods to determine decomposition progress in embalmed human cadavers.

Police in the United Kingdom received information that a person had gone missing. Despite a diligent search and investigation, the person was not found. Several years later police received intelligence giving the location of a grave believed to contain the remains of the person previously reported as missing and now believed to be a victim of homicide. This new information suggested the missing person had been murdered and their remains buried in shallow, unmarked grave. Following a systematic search, the murder victim’s body was found at a shallow depth, less than approximately 1 m. Following the forensic recovery of the body soil samples were collected at, beneath the floor of the grave, along strike of the grave, downslope and upslope. Analysis of the soil samples showed elevated levels of putrescine, at nearly 150 ppb in the soils beneath, downslope and for several meters upslope at localities where detector dogs had showed an ‘interest’ before the grave was discovered. The mineralogical analysis, using integrated automated mineralogy and petrology (QEMSCAN), detected the presence of diagenetic calcite in the soil profile beneath the grave. Additionally, the organic analysis detected the presence of elevated stanols at the grave site and down slope.