REFLECTIVE SPECTROSCOPY INVESTIGATIONS OF A COMMON COSMETIC BLUSH (WET'N'WILD) PROVIDE CONSTRAINTS FOR FORENSIC INVESTIGATIONS IN THE CONTEXT OF VIOLENCE AGAINST WOMEN AND OTHERS

Violence against women is a rising issue in today’s society and new approaches are being sought to combat the problem. Expanding forensic techniques is vital to increase the efficacy of recovering abducted victims, and gaining legal evidence such as proving or tracing contact between victims and suspects. This project aims to aid in the building of a new forensic technique in the context of violence against women using a field based reflective spectroscopy approach. The first step described here is to determine the detection limit of cosmetics when applied to certain materials with which violent or passive contact may be made. For this experiment, a common cosmetic, Wet’N’Wild Blush was used on various substrates, including a wood block, tulum (calcareous) sand, Ottawa sand, tile, Pergo wood, linoleum, closet material, carpets, and fabrics. A “push method” was developed in which various amounts of makeup were measured out (0.001 g, 0.002 g, 0.003 g, 0.005 g, 0.006 g, 0.007 g, 0.008 g, 0.009 g, 0.010 g, 0.030 g, 0.050 g, and 0.075 g), and then applied to each substrate using a template to control the area in which the makeup was applied. A gloved finger was used to forcefully push the makeup into the substrate, similar to how makeup would transfer by forcible contact in a forensics context. The reflective spectra data was collected using an ASD FieldSpec 4 and was then analyzed in detail. Interpretation of spectra was aided by electron microscopy and powder X-ray diffraction work on the blush sample. The data analyses in these experiments would be utilized along with hyperspectral images of crime scenes to determine if the blush signature was detected. This work demonstrates a novel method for investigating cosmetics in the context of violence against women and provides a foundation for future laboratory and field work using the ASD FieldSpec 4 and hyperspectral imaging systems.