Detection of Pb, Ba, and Sb in Cadaveric Maggots and Pupae by ICP‐MS*

Abstract

The concentrations of lead (Pb), barium (Ba), and antimony (Sb), characteristic of GSR, were determined in soil sediments and immature (larvae) of cadaveric flies of the family Calliphoridae, by inductively coupled plasma mass spectrometry (ICP-MS). This research refers to a case study from two real crime scenes in which the corpses were in an advanced state of decomposition. In case 1, the victim had holes similar to gunshot wounds, and in case 2, there was no evidence of perforations in the corpse. Soil sediment collection was performed at three different points of the terrain, at a minimum distance of 10 m from the corpse, for cases 1 and 2. In relation to the collection of immatures, larvae were collected in regions of the mouth, nose, and orifices similar to the entry of firearms projectile into the body, for case 1, and collection of larvae and pupae, located on the body and underneath it, for case 2. It was possible to detect and quantify the three elements of interest (Pb, Ba, and Sb) by ICP-MS in both sediment and cadaveric larvae. Concentrations of 4.44, 8.74, and 0.08 μg/g were obtained for Pb, Ba, and Sb, respectively, in the soil for case 1. For the case 2, the concentrations in Pb, Ba, and Sb were from 16.34 to 26.02 μg/g; from 32.64 to 57.97 μg/g and from 0.042 to 0.30 μg/g, respectively. In the larvae, Pb, Ba, and Sb were quantified in cases 1 and 2 with a concentration of 6.28 and 1.78 μg/g for Pb, 1.49 and 2.94 μg/g for Ba, 0.50 μg/g and <LD for Sb, respectively. These new results present the detection of characteristic elements of GSR in cadaveric larvae in humans in a real crime scene, besides highlighting the importance of the study of immature flies, using the ICP-MS technique in forensic analysis.

A review on the effects of heavy metals on the development of blow flies (Diptera: Calliphoridae)

“…Insects represent an effective matrix to detect those particles especially considering that colonization may indeed start in gunshot wounds and thus the GSR components may accumulate in their system as they feed on the corpse (Abd Rashid & Ahmad, 2012;LaGoo et al, 2010;Roeterdink et al, 2004). The importance of entomological evidence in cases where firearms were potentially used has been reported by Costa et al (2020). Their work describes two cases from Brazil where a decomposing body and a skeletonized body were found buried and exposed on a field, respectively; because of the conditions of the corpses, the forensic team was not able to assess the number and type of the injuries present.…”

Interpol Review of Gunshot Residue 2019 to 2021

“…So far, these analyses have been carried out most of the time in the context of studies. Costa et al report two examples where this technique was used in real cases [ 113 ]. While in one case the conclusions are unclear, in the second case it was possible to show that, despite the absence of other external evidence, the victim had been shot at close range by a firearm, due to a high concentration of the target elements.…”

Detection of Pb2+ in Tea Using Aptamer Labeled with AIEgen Nanospheres Based on MOFs Sensors

“…Up to the present, the methods used to detect heavy metal ions mainly include atomic absorption/emission spectrometry (AAS/AES) [ 4 , 5 ], mass spectrometry (MS) [ 6 ], inductively coupled plasma mass spectrometry (ICP-MS) [ 7 , 8 ], anodic stripping voltammetry (ASV) [ 9 ], high performance liquid chromatography (HPLC) [ 10 ], X-ray [ 11 ], etc. However, despite their high sensitivity and accuracy, these methods usually require specialized equipment, complex sample preparation, or time-consuming and laborious program operations that only professionals can perform.…”