Drug Analysis in Necrophagous Flies and Human Tissues

Abstract

Necrophagous insects may provide useful information about the time, place and cause of death. In addition, they can serve as reliable alternative specimens for toxicological analysis in cases where human tissue and fluids, normally taken during autopsies, are not available, due to decomposition of the corpse. This paper reports the results of drug analysis of the larvae of two fly families, Calliphoridae and Sarcophagidae, collected from the body of a middle-aged man who had committed suicide approximately three weeks before his corpse was found. Multiple samples of decomposed human tissue, of the blowfly, and of the larval flesh were analysed using gas chromatography/mass spectrometry (GC/MS), and amphetamine was detected in all samples. While the screening results were beyond doubt, the quantitative analysis was less clear, and further research is needed in this area.

Entomotoxicology, experimental set-up and interpretation for forensic toxicologists

“…At this point it is not possible to estimate the cause and circumstances of death from drug concentrations observed in insects reared on the corpse [6]. However, this relationship in human forensic cases is not yet established and still remains a controversy [6,13,14]. According to some authors, it seems hardly expected to find such a quantitative relationship due to a wide array of influencing factors which are largely unexplored and at the moment unpredictable [6].…”

“…This observation is logic as drugs are distributed in the body according to their physicochemical properties, leading to different drug concentrations in different organs and tissues, and thus also in insects reared on these different substrates. While most investigators [13,14] sample randomly, the best sampling sites for drug detection in insects are the internal organs (e.g. liver), the head-area or muscles in cases where no internal organs are left.…”

Forensically important flesh fly species in Thailand: morphology and developmental rate

“…Specifically, applied to forensic entomology, larvae of flesh flies have been reported for drug analysis (Definis-Gojanovic et al 2007) and implication in estimating the postmortem interval (Christopherson and Gibo 1997). In forensic entomology, identification of fly specimens found associating with the corpse is the first essential step; and the developmental rate of that fly species under temperature the same as (or close to) the crime scene is needed to estimate the postmortem interval (PMI).…”

“…Earlier investigations conducted with flesh flies concerning forensic entomology have involved various aspects, such as molecular/genetic identification (Wells et al 2001;Zehner et al 2004), effects of drugs in flesh fly development (Goff et al 1989(Goff et al , 1991(Goff et al , 1994(Goff et al , 1997Musvasva et al 2001), drug analysis of flesh fly larvae collected from human corpses (Definis-Gojanovic et al 2007), or developmental period (Byrd and Butler 1998;Marchenko 2001;Musvasva et al 2001;Villet et al 2006). Flesh flies involved in insect succession experiments have also been recorded.…”

Simultaneous determination of prescription drugs, cocaine, aldicarb and metabolites in larvae from decomposed corpses by LC–MS–MS after solid–liquid extraction with low temperature partitioning

“…The substances found include barbiturates [7], antidepressants and benzodiazepines [11], amphetamines [22], opiates [23], cocaine and its metabolite, benzoylecgonine [24,25], and pesticides [26]. The techniques used to determine these chemicals include gas chromatography coupled to a nitrogen-phosphorus detector [25] or mass spectrometry (MS) [24], and liquid chromatography coupled to a UV detector [23], MS [11], or MS-MS [9,27].…”