Absence of ethyl glucuronide (EtG) production in ethanol-fed Lucilia sericata (Diptera: Calliphoridae) larvae: a pilot study for forensic applications

Forensic entomotoxicology explores the role of necrophagous insects in toxicological investigations, particularly in cases where traditional samples are unavailable or compromised. This study investigates the ability of Lucilia sericata larvae to absorb ethanol and produce ethyl glucuronide (EtG) after feeding on ethanol-containing substrates. Ethanol was detected in the larvae, confirming its absorption, but EtG was not identified in either larvae or pupae. These findings indicate that the metabolic and excretory systems of larvae of Lucilia sericata (Meigen, 1826) (Diptera, Calliphoridae) are not responsible for producing EtG. This study underscores the importance of EtG as a marker of antemortem alcohol consumption when detected in larvae, as its presence reflects pre-existing levels in the cadaver rather than insect metabolism. These results highlight critical interpretative considerations for toxicological analyses and reinforce the need to understand the metabolic capacities of necrophagous insects in forensic investigations. This research contributes to the growing body of knowledge in entomotoxicology and its applications in postmortem toxicology.