Purpose <p>A principal objective of forensic entomotoxicology is to apply insect specimens for post-mortem toxicological analysis. Successful identification of drugs in necrophagous insects may depend on pharmacokinetic processes occurring in larvae. We thus applied a model system involving <i>Lucilia sericata</i> (Meigen, 1826) (Diptera, Calliphoridae) to investigate pharmacokinetics of diazepam in larvae in vitro, followed by a field experiment with Göttingen Minipigs.</p> Methods <p><i>Lucilia sericata</i> larvae were fed one of four diazepam concentrations at constant temperature, sampled regularly, and analysed for diazepam and metabolites by liquid chromatography tandem mass spectrometry (LC–MS/MS). Two Göttingen Minipigs of 60&#xa0;kg each were euthanised one hour after oral administration of 25&#xa0;mg/kg diazepam and placed outdoors. While available, samples of peripheral blood, cardiac blood, liver, and fly larvae were collected over 70&#xa0;days. Extracts from porcine samples and larvae were analysed by LC–MS/MS. Some larvae were bred to adulthood and identified morphologically together with 718 larvae.</p> Results <p>Oxazepam was a primary metabolite of diazepam in <i>L. sericata</i> larvae. The most prevalent fly species on minipig carcasses were <i>Lucilia caesar</i> (Linnaeus, 1758) (Diptera, Calliphoridae) and <i>Lucilia illustris</i> (Meigen, 1826) (Diptera, Calliphoridae). Diazepam and metabolites were detected in all larval samples, even weeks after porcine samples were unacquirable due to post-mortem decomposition. Ratios of oxazepam and nordazepam to diazepam concentrations in larvae were significantly higher than in associated porcine samples, confirming metabolism in larvae.</p> Conclusion <p>These findings are relevant to forensic casework, as there is potential for misinterpreting that the deceased consumed oxazepam or nordazepam rather than diazepam. This caution may also apply to other drugs that can form through metabolism in larvae.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Evaluating the value of entomotoxicology in forensic toxicology casework using the first minipig model

  • Olwen C. Groth,
  • Anaëlle Pi,
  • Andres E. Jensen,
  • Frank Reckel,
  • Jiri Hodecek,
  • Abderrahmane Kori Yahia,
  • Susan Rahaus,
  • Martin H. Villet,
  • Matthias Graw

摘要

Purpose

A principal objective of forensic entomotoxicology is to apply insect specimens for post-mortem toxicological analysis. Successful identification of drugs in necrophagous insects may depend on pharmacokinetic processes occurring in larvae. We thus applied a model system involving Lucilia sericata (Meigen, 1826) (Diptera, Calliphoridae) to investigate pharmacokinetics of diazepam in larvae in vitro, followed by a field experiment with Göttingen Minipigs.

Methods

Lucilia sericata larvae were fed one of four diazepam concentrations at constant temperature, sampled regularly, and analysed for diazepam and metabolites by liquid chromatography tandem mass spectrometry (LC–MS/MS). Two Göttingen Minipigs of 60 kg each were euthanised one hour after oral administration of 25 mg/kg diazepam and placed outdoors. While available, samples of peripheral blood, cardiac blood, liver, and fly larvae were collected over 70 days. Extracts from porcine samples and larvae were analysed by LC–MS/MS. Some larvae were bred to adulthood and identified morphologically together with 718 larvae.

Results

Oxazepam was a primary metabolite of diazepam in L. sericata larvae. The most prevalent fly species on minipig carcasses were Lucilia caesar (Linnaeus, 1758) (Diptera, Calliphoridae) and Lucilia illustris (Meigen, 1826) (Diptera, Calliphoridae). Diazepam and metabolites were detected in all larval samples, even weeks after porcine samples were unacquirable due to post-mortem decomposition. Ratios of oxazepam and nordazepam to diazepam concentrations in larvae were significantly higher than in associated porcine samples, confirming metabolism in larvae.

Conclusion

These findings are relevant to forensic casework, as there is potential for misinterpreting that the deceased consumed oxazepam or nordazepam rather than diazepam. This caution may also apply to other drugs that can form through metabolism in larvae.