QUANTIFICATION OF GSR IN BLOWFLY LARVAE BY ICP OES

Violence directly affects civil society. In Brazil firearms were used in 76,1% of all homicides in 2014. In this context, Forensic Ballistic takes on a role of great legal and social relevance, acting as a legal instrument to elucidate the dynamics and authorship of crimes involving the use of firearms [1]. In Forensic Sciences, Entomology has been highlighted in studies of insects and arthropods associated with criminal matters Entomological evidence in corpses has helped to elucidate murders, such as postmortem interval that contributes to the location and time of death in a homicide or suicide [1]. Thus, in many cases, Ballistic and Forensic Entomology may be associated, increasing crime solution. Larvae were collected, which were stored in Polypropylene tubes containing 10 mL of ethanol 70% (v/v) for organic matter preservation. Microwave assisted digestion (Anton Paar, MultiwaveGo Autria) of the samples was carried out by adding 3 mL HNO3, 1 mL H2O2 and 4 mL H2O. Finally, the samples were transferred to polypropylene tubes, 6 mL of ultrapure water was added, and the samples were analyzed. An ICP OES (PerkinElmer, Model Optima 7000, USA) was used for the quantification of Pb, Ba, and Sb. A SeaSpray U-Series concentric nebulizer and cyclonic spray chamber with peristaltic pumping were used for introducing the samples into the plasma torch. The operating parameters were optimized using a central composite design [2]. Inductively coupled plasma-optical emission spectrometry (ICP OES) is a powerful tool for GSR analysis, providing multielemental quantification of lead (Pb), barium (Ba), and antimony (Sb). It was possible to quantify Pb, Ba and Sb concentrations in all samples.