RESUMO
ABSTRACT Entomofauna associated with decaying cadavers may be useful in criminal investigation, either through the development of immature insects of interest or through entomological succession in corpses. These factors may vary if the insects are exposed to toxic substances that can modify the insect's developmental cycle, as well as its own occurrence, which would imply significant changes in the results of any investigation. However, there are few studies on how contamination by toxic compounds can affect the action of insects on carcasses and their consequence for forensic expertise. Therefore, this study aimed to test the hypothesis that the normal visitation of flies and beetles is altered in insecticide-contaminated carcasses. The experiment was carried out in a sugarcane plantation, using pig carcasses contaminated with insecticide and the same number of carcasses without any type of contamination as a control. In all experiments, the contaminated carcasses reached the final phase of decomposition in a longer time than the uncontaminated carcasses of the control group. A total of 2.767 specimens were collected and identified, 2.103 individuals from the order Diptera and 664 from the order Coleoptera. There was a significant geometric regression adjustment during the decomposition phases only for the control group, different from the contaminated carcasses in which this pattern did not occur. Results show that contamination by insecticide alters decomposition time and phase, altering the action of flies and beetles, affecting the abundance, composition of species as well as their activities, which can alter the data used by experts in criminal experts.
RESUMO
Entomotoxicology is the analysis of toxins in arthropods (mainly flies and beetles) that feed on carrion. Careful analyses of the community of insects encountered on a decomposing body, combined with knowledge of insect biology, ecology, and local environmental conditions can often provide valuable forensic insights. These can include the estimation of time since death, movement of the remains after death, indication of ante mortem injuries, and the presence of drugs or toxins. The accuracy of entomological estimates in deaths involving narcotic intoxication has been subject to debate in recent years as few available studies have explored the effects of drugs contained in decomposing tissues on fly colonization and ovipositional behavior, or on the rates of development of carrion-frequenting insects feeding on such food sources. Additionally, relatively few studies have examined the effects of other tissue contaminants, such as toxins or environmental pollutants, on these behaviors and/or the developmental patterns of the insects colonizing such tissues. Studies of the use of carrion-feeding arthropods as alternative toxicological specimens and of the impact that tissue toxins and contaminants have on the development of immature insects feeding on these substances currently comprise the major avenues of exploration in the emerging field of entomotoxicology