A multitechnique approach for discrimination and identification of lipsticks for forensic purposes

Abstract

Cosmetics are becoming more and more popular; consequently, the chance of finding them as microtraces at a crime scene increases. They are easily transferable and can provide a link between a suspect and a victim. For this reason, identifying and comparative analysis of red lipstick – the most popular and used – is required. The aim of this study was to apply a multitechnique methodology for the comparative forensic analysis of the red lipsticks traces of a very similar hue. For this purpose, four methods of different physicochemical basics – two nondestructive spectroscopic and two destructive separation techniques – were used. The possibilities and advantages of attenuated total reflection infrared spectroscopy (ATR‐FTIR), confocal Raman microscopy (CRM), capillary electrophoresis (MEKC) and gas chromatography‐mass spectrometry (GC‐MS) have been combined. Specially prepared lipstick traces in various forms (imprints, smears) on different surfaces (absorbent and nonabsorbent) were analyzed to confirm the usefulness of the proposed methods. The premise is that if two methods yield a consistent result, the investigation is terminated at this stage. All investigated traces were properly identified. First, the ATR‐FTIR method as a nondestructive technique is recommended. Sometimes, due to strong interferences from the substrates, the newly proposed method with the use of confocal Raman microscopy may be an alternative. The next recommendation is the MEKC method. Only in case of the absence of unambiguous conclusions, it is proposed to use the GC‐MS method. This methodology has the potential to be applied in the comparative analysis of red lipsticks for forensic purposes.

Innovative Vibrational Spectroscopy Research for Forensic Application

“…Additional work done by Gładysz et al included the development of a multitechnique approach to discriminate against red lipstick. 97 Their research established that ATR-FTIR spectroscopy should be an initial step in the analysis plan of lipstick, as it is a nondestructive technique. However, substrate interference may cause problems in certain cases and would require additional analysis.…”

“…Despite the various storage conditions, ATR-FTIR spectroscopy was able to identify the remnant lipstick traces. Additional work done by Gładysz et al included the development of a multitechnique approach to discriminate against red lipstick . Their research established that ATR-FTIR spectroscopy should be an initial step in the analysis plan of lipstick, as it is a nondestructive technique.…”

Forensic examination of lipsticks as trace evidence under different environmental conditions

“…The discrimination of chemical composition of lip cosmetic products is critical parameter to solve criminal cases in forensic science. For this, various methods such as atomic absorption spectrometry (AAS), inductively coupled plasma mass spectrometry (ICP-MS), thin layer chromatography (TLC), gas chromatography-mass spectrometry (GC-MS), high performance liquid chromatography (HPLC), Fourier-transform infrared spectroscopy (FTIR) have been performed to differentiate the cosmetic evidence [22][23][24].…”

New Applications of Gas Chromatography and Gas Chromatography-Mass Spectrometry for Novel Sample Matrices in the Forensic Sciences: A Literature Review

“…The review covers recent advances in both GC and GC-MS applications applicable to the forensic discipline. The applications discussed include sweat and skin [37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52], cerumen [53][54][55][56], meconium [57][58][59], breast milk [60,61], larvae, pupae and insects [62][63][64][65], Vitreous humour [66][67][68][69][70][71], drug paraphernalia [72] cosmetics and fragrances [73][74][75][76][77][78], and air, gases and vapours [79][80][81][82][83][84]. A further section is dedicated to the application of pyrolysis GC-MS…”