Forensic entomotoxicology: Where are we going? 30 years in a review

Forensic entomotoxicology, which was first mentioned in a publication in 1994, focuses on the detection of drugs and toxins in necrophagous insects to provide valuable information in a variety of areas. This discipline faces fundamental limitations as its findings are often not easily transferable to practical contexts, thereby necessitating a case-specific approach for effective application. To overcome these challenges, a systematic review of scientific literature available on 31 December 2024 was conducted in order to summarise strengths and weaknesses of forensic entomotoxicology in accordance with the PRISMA guidelines. After 81 relevant sources were selected, four main lines of research in entomotoxicology were identified: 1) effects of exogenous substances on larvae and, consequently, how the estimated minPMI (minimum Post-Mortem Interval) should be adjusted, 2) identification of cause of death, 3) study of the impact of exogenous substances on the environment using larval masses and 4) possible methods for analysing larvae to identify the substances they contain. Overall, findings are heterogeneous and sometimes contradictory, indicating that exogenous substances can influence larval development and be detected in entomological samples, but in ways that are strongly species-, substance- and context-dependent and not yet robust enough for straightforward extrapolation to casework. By critically synthesising these issues, this review clarifies the main strengths and recurring limitations of forensic entomotoxicology and indicates when its use may be informative, when it should be interpreted with caution, and which methodological issues need to be addressed in future research.